Japanese grammar#Adjectives

The modern theory of constituent order ("word order"), usually attributed to Joseph Harold Greenberg, identifies several kinds of phrases. Each one has a head and possibly a modifier. The head of a phrase either precedes its modifier (head-initial) or follows it (head-final). Some of these phrase types, with the head marked in boldface, are:

• genitive phrase, i.e., noun modified by another noun ("the cover of the book", "the book's cover");
• noun governed by an adposition ("on the table", "underneath the table");
• comparison ("[X is] bigger than Y", i.e., "compared to Y, X is big").
• noun modified by an adjective ("black cat").

Some languages are inconsistent in constituent order, having a mixture of head-initial phrase types and head-final phrase types. Looking at the preceding list, English for example is mostly head-initial, but nouns follow the adjectives which modify them. Moreover, genitive phrases can be either head-initial or head-final in English. By contrast, the Japanese language is consistently head-final:

• genitive phrase:

{{fs interlinear|lang=ja|indent=3

|猫 の 色

|neko no iro

|cat GEN color

|"the cat's ({{transliteration|ja|neko no}}) color ({{transliteration|ja|iro}})"}}

• noun governed by an adposition:

{{fs interlinear|lang=ja|indent=3

|日本 に

|nihon ni

|Japan in

|"in Japan"}}

• comparison:

{{fs interlinear|lang=ja|indent=3

|Y より 大きい

|Y yori ookii

|{{no gloss|Y}} than big

|"bigger than Y"}}

• noun modified by an adjective:

{{fs interlinear|lang=ja|indent=3

|黒い 猫

|kuroi neko

|black cat|}}

Head-finality in Japanese sentence structure carries over to the building of sentences using other sentences. In sentences that have other sentences as constituents, the subordinated sentences (relative clauses, for example), always precede what they refer to, since they are modifiers and what they modify has the syntactic status of phrasal head. Translating the phrase "the man who was walking down the street" into Japanese word order would be "street down walking was man".{{efn|Note that Japanese has no articles, and the different word order obviates any need for the relative pronoun who.}}

Head-finality prevails also when sentences are coordinated instead of subordinated. In the world's languages, it is common to avoid repetition between coordinated clauses by optionally deleting a constituent common to the two parts, as in "Bob bought his mother some flowers and his father a tie", where the second bought is omitted. In Japanese, such "gapping" must proceed in the reverse order: "Bob mother for some flowers and father for tie bought". The reason for this is that in Japanese, sentences (other than occasional inverted sentences or sentences containing afterthoughts) always end in a verb (or other predicative words like adjectival verbs, adjectival nouns, auxiliary verbs)—the only exceptions being a few sentence-ending particles such as {{transliteration|ja|ka}}, {{transliteration|ja|ne}}, and {{transliteration|ja|yo}}. The particle {{transliteration|ja|ka}} turns a statement into a question, while the others express the speaker's attitude towards the statement.

Japanese has five major lexical word classes:

• {{Nihongo|nouns|名詞|meishi}}
• verbal nouns (correspond to English gerunds like 'studying', 'jumping', which denote activities)
• {{Nihongo|adjectival nouns|形容動詞|keiyō dōshi}} (names vary, also called {{transliteration|ja|na}}-adjectives or "nominal adjectives")
• verbs
• {{Nihongo|adjectives|形容詞|keiyōshi}} (so-called {{transliteration|ja|i}}-adjectives)

More broadly, there are two classes: uninflectable (nouns, including verbal nouns and adjectival nouns) and inflectable (verbs, with adjectives as defective verbs). To be precise, a verbal noun is simply a noun to which the light verb {{Nihongo3|"do"|する|suru}} can be appended, while an adjectival noun is like a noun but uses {{Nihongo3||〜な|-na}} instead of {{Nihongo3||〜の|-no}} when acting attributively. Adjectives ({{transliteration|ja|i}}-adjectives) inflect identically to the negative form of verbs, which end in {{Nihongo3||ない|na-i}}. Compare {{Nihongo3|don't eat|食べない|tabe-na-i}} → {{Nihongo3|didn't eat|食べなかった|tabe-na-katta}} and {{Nihongo3|is hot|熱い|atsu-i}} → {{Nihongo3|was hot|熱かった|atsu-katta}}.

Some scholars, such as Eleanor Harz Jorden, refer to adjectives instead as adjectivals, since they are grammatically distinct from adjectives: they can predicate a sentence. That is, {{Nihongo3||熱い|atsui}} is glossed as "hot" when modifying a noun phrase, as in {{Nihongo3|hot food|熱いご飯|atsui gohan}}, but as "is hot" when predicating, as in {{Nihongo3|[the] food is hot|ご飯は熱い|gohan wa atsui}}.

The two inflected classes, verb and adjective, are historically considered closed classes, meaning they do not readily gain new members—but see the following paragraphs.{{sfn|Uehara|1998|p=76}}{{sfn|Dixon|1977|p=48}} Instead, new and borrowed verbs and adjectives are typically conjugated periphrastically as verbal noun + {{transliteration|ja|suru}} (e.g. {{Nihongo3|do studying; study|勉強する|benkyō suru}}) and adjectival noun + {{transliteration|ja|na}}. This differs from Indo-European languages, where verbs and adjectives are open classes, though analogous "do" constructions exist, including English "do a favor", "do the twist" or French "faire un footing" (do a "footing", go for a jog), and periphrastic constructions are common for other senses, like "try climbing" (verbal noun) or "try parkour" (noun). Other languages where verbs are a closed class include Basque: very few Basque verbs (albeits very common ones) have synthetic conjugation, all the others are only formed periphrastically. Conversely, pronouns are closed classes in Western languages but open classes in Japanese and some other East Asian languages.

In a few cases historically, and much more commonly recently, new verbs are created by appending the suffix {{Nihongo3||〜る|-ru}} to a noun or using it to replace the end of a word. This is most often, but not exclusively, done with borrowed words, and results in a word written in a mixture of katakana (stem) and hiragana (inflectional ending), which is otherwise very rare.{{cite web |url=http://japaneselevelup.com/homage-to-るru-the-magical-verbifier/ |title=Homage to る(ru), The Magical Verbifier |date= 2011-07-18 |author=Adam|work=Japanese Level Up }} This is typically casual, with the most well-established example being {{Nihongo3|skip class; play hooky|サボる|sabo-ru}} (circa 1920), from {{Nihongo3|sabotage|サボタージュ|sabotāju}}, with other common examples including {{Nihongo3|write a memo|メモる|memo-ru}}, from {{Nihongo|memo|メモ}}, and {{Nihongo3|make a mistake|ミスる|misu-ru}} from {{Nihongo3|mistake|ミス|misu}}. In cases where the borrowed word already ends with or even contains a {{Nihongo3||ル|ru}} or {{Nihongo3||リ|ri}}, this may be rebracketed as a verb ending and changed to a {{Nihongo3||る|ru}}, as in {{Nihongo3|to google|ググる|gugu-ru}}, from {{Nihongo3|Google|グーグル|gūguru}}; {{Nihongo3|to double|ダブる|dabu-ru}}, from {{Nihongo3|double|ダブル|daburu}}; and {{Nihongo3|to favorite (e.g. a tweet)|ファボる|fabo-ru>}}, from {{Nihongo3|favorite|ファボリート|faboriito}}.{{cite web |title =「ディスる」「タクる」は70%が聞いたことがないと回答 国語世論調査で判明|trans-title=70% of Japanese people have never heard of the words taku-ru and disu-ru. |url = http://nlab.itmedia.co.jp/nl/articles/1409/25/news148.html | access-date = 2016-01-20 }}{{cite web|title=morphology - Characteristics of 'loan word root + る' verbs - Japanese Language StackExchange|url=https://japanese.stackexchange.com/questions/66495/characteristics-of-loan-word-root-%E3%82%8B-verbs|access-date=2025-01-27}} New verbs coined in this fashion are uniformly group 1 verbs and, at least in the Tokyo accent, consistently are stressed immediately before the final る.

New adjectives are extremely rare; one example is {{Nihongo3|yellow|黄色い|kiiro-i}}, from adjectival noun {{Nihongo3||黄色|kiiro}}, and a more casual recent example is {{Nihongo3|gross|きもい|kimo-i}}, by contraction of {{Nihongo3|bad-feeling|気持ち悪い|kimochi waru-i}}.[http://linguistics.stackexchange.com/questions/9012/languages-with-different-open-and-closed-word-classes Languages with different open and closed word classes] By contrast, in Old Japanese {{Nihongo3||〜しき|-shiki}} adjectives (precursors of present {{transliteration|ja|i}}-adjectives ending in {{Nihongo3||〜しい|-shi-i}}, formerly a different word class) were open, as reflected in words like {{Nihongo3|pitiful|痛々しい|ita-ita-shi-i}}, from the adjective {{Nihongo3|painful, hurt|痛い|ita-i}}, and {{Nihongo3|heavenly, sublime|神々しい|kō-gō-shi-i}}, from the noun {{Nihongo3|god|神|kami}} (with sound change). Japanese adjectives are unusual in being closed class but quite numerous – about 700 adjectives – while most languages with closed class adjectives have very few.The Typology of Adjectival Predication, Harrie Wetzer, [https://books.google.com/books?id=ORUUwhdDPpUC&pg=PA311 p. 311]The Art of Grammar: A Practical Guide, Alexandra Y. Aikhenvald, [https://books.google.com/books?id=XFBVBQAAQBAJ&pg=PA96 p. 96] Some believe this is due to a grammatical change of inflection from an aspect system to a tense system, with adjectives predating the change.

The conjugation of {{transliteration|ja|i}}-adjectives has similarities to the conjugation of verbs, unlike Western languages where inflection of adjectives, where it exists, is more likely to have similarities to the declension of nouns. Verbs and adjectives being closely related is unusual from the perspective of English, but is a common case across languages generally, and one may consider Japanese adjectives as a kind of stative verb.

Japanese vocabulary has a large layer of Chinese loanwords, nearly all of which go back more than one thousand years, yet virtually none of them are verbs or "{{transliteration|ja|i}}-adjectives" – they are all nouns, of which some are verbal nouns ({{transliteration|ja|suru}}) and some are adjectival nouns ({{transliteration|ja|na}}). In addition to the basic verbal noun + {{transliteration|ja|suru}} form, verbal nouns with a single-character root often experienced sound changes, such as {{Nihongo3||〜する|-suru}} → {{Nihongo3||〜ずる|-zuru}} (rendaku) → {{Nihongo3||〜じる|-jiru}}, as in {{Nihongo3|forbid|禁じる|kin-jiru}}, and some cases where the stem underwent sound change, as in {{Nihongo3|reach|達する|tassuru}}, from {{Nihongo3||達|tatsu}}.

Verbal nouns are uncontroversially nouns, having only minor syntactic differences to distinguish them from pure nouns like 'mountain'. There are some minor distinctions within verbal nouns, most notably that some primarily conjugate as {{Nihongo3||〜をする|-o suru}} (with a particle), more like nouns, while others primarily conjugate as {{Nihongo3||〜する|-suru}}, and others are common either way. For example, {{Nihongo3|to experience|経験をする|keiken o suru}} is much more common than {{Nihongo3||経験する|keiken suru}}, while {{Nihongo3|to pardon|勘弁する|kanben suru}} is much more common than {{Nihongo3||勘弁をする|kanben o suru}}.{{Cite web |url=http://aveneca.com/cbb/viewtopic.php?f=8&t=3855 |title=Closed and open classes in Natlangs (Especially Japanese) |access-date=February 22, 2015 |archive-url=https://web.archive.org/web/20150222070657/http://aveneca.com/cbb/viewtopic.php?f=8&t=3855 |archive-date=February 22, 2015 |url-status=dead }} Adjectival nouns have more syntactic differences versus pure nouns, and traditionally were considered more separate, but they, too, are ultimately a subcategory of nouns.

There are a few minor word classes that are related to adjectival nouns, namely the taru adjective and naru adjective. Of these, {{transliteration|ja|naru}} adjectives are fossils of earlier forms of {{transliteration|ja|na}} adjectives (the {{transliteration|ja|nari}} adjectives of Old Japanese), and are typically classed separately, while {{transliteration|ja|taru}} adjectives are a parallel class (formerly {{transliteration|ja|tari}} adjectives in Late Old Japanese), but are typically classed with {{transliteration|ja|na}} adjectives.

The first structured description of the Japanese {{nihongo|parts of speech|品詞|hinshi}} was in {{nihongo||語學新書|Gogaku Shinsho}}, an 1831 grammar by Tsurumine Shigenobu.{{cite book|title=日本語𭓘史|date=December 1908|last=長|first=連恒|url=https://dl.ndl.go.jp/pid/862087/1/39|page=68|publisher=Hakubunkan|language=Japanese}} It was based on earlier Dutch grammars such as Shizuki Tadao's {{nihongo||和蘭詞品考|Oranda Shihin Kō|{{lit|Study of the Dutch Parts of Speech}}, 1798}} and {{nihongo||蘭語九品集|Rango Kyūhin Shū|{{lit|Compilation of the Nine Dutch Parts of Speech}}, date unknown}}. The words hinshi and shihin also came about from these early late-Edo and early-Meiji grammars. Since then, there have been multiple conflicting classifications of the parts of speech of Japanese.

The term {{nihongo||形容動詞|keiyō dōshi|{{lit|adjectival verb}}}} assumed different meanings, such as a verb form ({{nihongo||連用形|ren'yōkei}}{{cite book|url=https://dl.ndl.go.jp/pid/992603/1/16|page=18|year=1887|title=副假字法規|last=Hamada|first=Kenjirō|publisher=Tetsugaku Shoin|language=Japanese}} or {{nihongo||連体形|rentaikei}}{{cite book|url=https://dl.ndl.go.jp/pid/864215/1/38|page=37|date=April 1891|title=和文典|volume=2|last=Ōwada|first=Takeki|publisher=Chūōdō|language=Japanese}}) that precedes a noun, or as a proposed alternative to {{nihongo||形容詞|keiyōshi}}, because Japanese "adjectives" are verb-like in nature, unlike European adjectives.{{cite book|url=https://dl.ndl.go.jp/pid/992498/1/61|page=80|last=Ōtsuki|first=Fumihiko|year=1897|title=廣日本文典 別記|language=Japanese}}{{cite book|url=https://dl.ndl.go.jp/pid/810429/1/55|page=97|date=February 1893|last=萩井|first=重次|publisher=盛文館|title=尋常高等教授細目及教授法|language=Japanese}} As shown in the table, Matsushita Daizaburō (1924) used keiyōshi explicitly for the Eurocentric idea of adjectives as words that precede nouns, while reserving keiyō dōshi for Japanese "adjectives" as verb-like words (although later in 1928, he swapped out keiyōshi for {{nihongo||副體詞|fukutaishi}} to avoid confusion, on the model of {{nihongo||副詞|fukushi}} as words that precede verbs). Ochiai Naobumi (1895) defined keiyō dōshi not as a grammatical category, but as a semantic one with meanings similar to those of stative verbs ({{nihongo||落花雪に似たり|rakka yuki-ni nitari|{{lit|as for falling flowers, they are like snow}}}}, {{nihongo||山は遠方に在り|yama-wa enpō-ni ari|{{lit|as for the mountain, it is far away}}}}).{{cite book|url=https://dl.ndl.go.jp/pid/864051/1/16|pages=27–28|title=日本大文典|volume=2|date=26 March 1895|publisher=Hakubunkan|last=Ochiai|first=Naobumi|language=Japanese}} It was not until Haga Yaichi's usage in 1905 that keiyō dōshi came to be refer to adjectival words whose {{nihongo||終止形|shūshikei}} ended with {{nihongo||なり|nari}} or {{nihongo||たり|tari}}{{cite book|title=日本語文法大辞典|language=Japanese|editor-last=Yamaguchi|editor-first=Akiho|editor-last2=Akimoto|editor-first2=Morihide|publisher=Meiji Shoin|date=1 March 2001}}{{cite book|language=Japanese|date=24 February 1905|last=Haga|first=Yaichi|url=https://dl.ndl.go.jp/pid/992202/1/25|page=35|publisher=Fuzanbō|title=中等教科明治文典|volume=1}} (in modern Japanese, they end with {{nihongo||だ|da}}).

The {{nihongo||学校文法|gakkō bunpō|{{lit|school grammar}}}} of today has followed Iwabuchi Etsutarō's model outlined in his 1943 grammar, {{nihongo||中等文法|Chūtō Bunpō}}, compiled for the {{nihongo|Ministry of Education, Science, Sports and Culture|文部省|Monbushō}}.{{cite thesis|last=Morita|first=Shingo|date=26 July 2021|language=Japanese|title=「学校文法」成立過程における指導内容の生成と収斂|degree=Doctor of Philosophy in Education|url=https://tsukuba.repo.nii.ac.jp/record/2000707/files/DB02992.pdf|publisher=University of Tsukuba|id=10.15068/0002000707}} It recognizes 10 parts of speech as shown in the table.

Among historical classifications, the grammarian Matsushita Daizaburō notably compared his own terminology to the terminologies translated from and modeled after European ones at the time.{{cite book|url=https://dl.ndl.go.jp/pid/982965/1/156|page=290|title=標準日本文法|last=Matsushita|first=Daizaburō|date=31 December 1924|publisher=Kigensha}}{{cite book|url=https://dl.ndl.go.jp/pid/1225783/1/180|page=323|title=改撰標準日本文法|last=Matsushita|first=Daizaburō|date=25 April 1928|publisher=Kigensha}}{{cite book|url=https://dl.ndl.go.jp/pid/1178361/1/45|page=59|title=標準日本口語法|last=Matsushita|first=Daizaburō|date=27 February 1930|publisher=Chūbunkan Shoten}} In particular, he rejected the equation of what were dubbed {{nihongo||形容詞|keiyōshi}} in Japanese to the concept of "adjectives" in European grammars, although he revised his systems over the years, which ended up conforming to the popular usage of the term keiyōshi. According to Matsushita (1930):

In discourse pragmatics, the term topic refers to what a section of discourse is about. At the beginning of a section of discourse, the topic is usually unknown, in which case it is usually necessary to explicitly mention it. As the discourse carries on, the topic need not be the grammatical subject of each new sentence.

Starting with Middle Japanese, the grammar evolved so as to explicitly distinguish topics from nontopics. This is done by two distinct particles (short words which do not change form). Consider the following pair of sentences:

{{fs interlinear|indent=3|lang=ja|transl=Hepburn|glossing=no abbr

|犬 が サンド を 食べている。

|inu ga sando o tabeteiru

|dog NONTOPIC sandwich OBJ eat|}}

{{fs interlinear|indent=3|lang=ja|transl=Hepburn|glossing=no abbr

|犬 は サンド を 食べている。

|inu wa sando o tabeteiru

|dog TOPIC sandwich OBJ eat|}}

In the first sentence {{nihongo|the dog|犬|inu}} is not a discourse topic—not yet; in the second sentence it is a discourse topic. In linguistics (specifically, in discourse pragmatics) a sentence such as the second one (with {{transliteration|ja|wa}}) is termed a presentational sentence because its function in the discourse is to present dog as a topic, to "broach it for discussion". Once a referent has been established as the topic of the current monolog or dialog, then in (formal) modern Japanese its marking will change from {{transliteration|ja|ga}} to {{transliteration|ja|wa}}.

To better explain the difference, the first sentence can be translated to "There's a dog eating a sandwich", while the second sentence can be translated to "You know the dog? It's eating a sandwich"; these renderings reflect a discourse fragment in which "the dog" is being established as the topic of an extended discussion. The first sentence answers the question "What is going on?," whereas the second sentence answers the question "What is the dog doing?"

The grammatical subject is commonly omitted in Japanese, as in

{{fs interlinear|indent=3|lang=ja|transl=Hepburn

|日本 に 行きました

|nihon ni ikimashita

|Japan LOC go-POL-PFV

|went to Japan}}

Subjects are mentioned when a topic is introduced, or in situations where an ambiguity might result from their omission. The preceding example sentence would most likely be uttered in the middle of a discourse, where who it is that "went to Japan" will be clear from what has already been said (or written).

{{nihongo|Text|文章|bunshō}} is composed of {{nihongo|sentences|文|bun}}, which are in turn composed of {{nihongo|phrases|文節|bunsetsu}}, which are its smallest coherent components. Like Chinese and classical Korean, written Japanese does not typically demarcate words with spaces; its agglutinative nature further makes the concept of a word rather different from words in English. The reader identifies word divisions by semantic cues and a knowledge of phrase structure. Phrases have a single meaning-bearing word, followed by a string of suffixes, auxiliary verbs and particles to modify its meaning and designate its grammatical role.

{{fs interlinear|indent=3|lang=ja|transl=Hepburn

|太陽が 東の 空に 昇る。

|{taiyō ga} {higashi no} {sora ni} noboru

|{sun SBJ} {east POSS} {sky LOC} rise

|The sun rises in the eastern sky.}}

Some scholars romanize Japanese sentences by inserting spaces only at phrase boundaries (i.e., "{{transliteration|ja|taiyō-ga higashi-no sora-ni noboru}}"), treating an entire phrase as a single word. This represents an almost purely phonological conception of where one word ends and the next begins. There is some validity in taking this approach: phonologically, the postpositional particles merge with the structural word that precedes them, and within a phonological phrase, the pitch can have at most one fall. Usually, however, grammarians adopt a more conventional concept of {{nihongo|word|単語|tango}}, one which invokes meaning and sentence structure.

In Japanese, phrasal constituents can be moved to the beginning or the end of the sentence. Leftward movement of a phrasal constituent is referred to as "scrambling".

In linguistics generally, words and affixes are often classified into two major word categories: lexical words, those that refer to the world outside of a discourse, and function words—also including fragments of words—which help to build the sentence in accordance with the grammar rules of the language. Lexical words include nouns, verbs, adjectives, adverbs, and sometimes prepositions and postpositions, while grammatical words or word parts include everything else. The native tradition in Japanese grammar scholarship seems to concur in this view of classification. This native Japanese tradition uses the terminology {{Nihongo3|independent words|自立語|jiritsugo}}, for words having lexical meaning, and {{Nihongo3|auxiliary words|付属語|fuzokugo}}, for words having a grammatical function.

Classical Japanese had some auxiliary verbs (i.e., they were independent words) which have become grammaticized in modern Japanese as inflectional suffixes, such as the past tense suffix {{transliteration|ja|-ta}} (which might have developed as a contraction of {{transliteration|ja|-te ari}}).

Traditional scholarship proposes a system of word classes differing somewhat from the above-mentioned.{{Citation needed|date=March 2009}} The "independent" words have the following categories.

: {{Nihongo3||活用語|katsuyōgo}}, word classes which have inflections

:: {{Nihongo3||動詞|dōshi}}, verbs

:: {{Nihongo3||形容詞|keiyōshi}}, {{transliteration|ja|i}}-type adjectives

:: {{Nihongo3||形容動詞|keiyōdōshi}}, {{transliteration|ja|na}}-type adjectives

: {{Nihongo3||非活用語|hikatsuyōgo}} or {{Nihongo3||無活用語|mukatsuyōgo}}, word classes which do not have inflections{{Citation needed|date=March 2009}}

:: {{Nihongo3||名詞|meishi}}, nouns

:: {{Nihongo3||代名詞|daimeishi}}, pronouns

:: {{Nihongo3||副詞|fukushi}}, adverbs

:: {{Nihongo3||接続詞|setsuzokushi}}, conjunctions

:: {{Nihongo3||感動詞|kandōshi}}, interjections

:: {{Nihongo3||連体詞|rentaishi}}, prenominals

Ancillary words also divide into a nonconjugable class, containing {{nihongo|grammatical particles|助詞|joshi}} and {{nihongo|counter words|助数詞|josūshi}}, and a conjugable class consisting of {{nihongo|auxiliary verbs|助動詞|jodōshi}}. There is not wide agreement among linguists as to the English translations of the above terms.

Uehara (1998){{sfn|Uehara|1998|loc=chapter 2, especially §2.2.2.2}} observes that Japanese grammarians have disagreed as to the criteria that make some words inflectional and others not, in particular, the adjectival nouns – {{nihongo||形容動詞|keiyōdōshi}} or {{transliteration|ja|na}}-adjectives. (It is not disputed that nouns like {{transliteration|ja|hon}} 'book' are non-inflectional and that verbs and {{transliteration|ja|i}}-adjectives are inflectional.) The claim that adjectival nouns are inflectional rests on the claim that the element {{transliteration|ja|da}}, regarded as a copula by proponents of non-inflectional adjectival nouns, is really a suffix—an inflection. That is, {{nihongo3|'it is pretty'||kireida}} is a one-word sentence, not a two-word sentence, {{transliteration|ja|kirei da}}. However, numerous constructions show that {{transliteration|ja|da}} is less bound to the roots of nouns and adjectival nouns than {{transliteration|ja|-i}} and {{transliteration|ja|-(r)u}} are to the roots of {{transliteration|ja|i}}-adjectives and verbs, respectively.

:(1) Reduplication for emphasis

::{{nihongo3|'See! It {{em|is}} a book!'||Hora! Hon, hon!}}

::{{nihongo3|'See! It {{em|is}} pretty!'||Hora! Kirei, kirei!}}

::{{nihongo3|'See! It {{em|is}} old!'||Hora! Furu-i, furu-i!}} (the adjectival inflection {{transliteration|ja|-i}} cannot be left off)

::{{nihongo3|'See! It {{em|does}} go!'||Hora! Ik-u, ik-u!}} (the verbal inflection {{transliteration|ja|-u}} cannot be left off)

:(2) Questions. In Japanese, questions are formed by adding the particle {{transliteration|ja|ka}} (or in colloquial speech, just by changing the intonation of the sentence).{{Cite web |last=平山 |first=仁美 |title=Rising Declaratives in Japanese |url=https://researchmap.jp/h_hirayama/published_papers/41250203 |archive-url=https://web.archive.org/web/20231108202903/https://web.stanford.edu/group/cslipublications/cslipublications/site/JKONLINE/29/CH12.pdf |archive-date=2023-11-08 |access-date=2023-11-08 |website=researchmap.jp}}

::{{nihongo3|'Is it a book?'||Hon ka?}}

::{{nihongo3|'Is it pretty?'||Kirei ka?}}

::{{nihongo3|'Is it old?||Furu-i ka?}} ({{transliteration|ja|-i}} cannot be left off)

::{{nihongo3|'Does it go?'||Ik-u ka?}} ({{transliteration|ja|-u}} cannot be left off)

:(3) Several epistemic modality predicates, e.g., {{nihongo3|'seem like'||mitai}}

::{{nihongo3|'It seems to be a book'||Hon mitai da}}

::{{nihongo3|'It seems to be pretty'||Kirei mitai da}}

::{{nihongo3|'It seems to be old'||Furu-i mitai da}} ({{transliteration|ja|-i}} cannot be left off)

::{{nihongo3|'It seems to go'||Ik-u mitai da}} ({{transliteration|ja|-u}} cannot be left off)

On the basis of such constructions, Uehara finds that the copula {{transliteration|ja|da}} is not suffixal and that adjectival nouns pattern with nouns in being non-inflectional.

Similarly, Eleanor Jorden considers this class of words a kind of nominal, not adjective, and refers to them as {{transliteration|ja|na}}-nominals in her textbook Japanese: The Spoken Language.

{{see also|Honorific speech in Japanese}}

Japanese has no grammatical gender, number, or articles; though the demonstrative {{nihongo3|"that, those"|その|sono}}, is often translatable as "the". Thus, linguists agree that Japanese nouns are noninflecting: {{nihongo||猫|neko}} can be translated as "cat", "cats", "a cat", "the cat", "some cats" and so forth, depending on context. However, as part of the extensive pair of grammatical systems that Japanese possesses for honorification (making discourse deferential to the addressee or even to a third party) and politeness, nouns too can be modified. Nouns take politeness prefixes (which have not been regarded as inflections): {{transliteration|ja|o-}} for native nouns, and {{transliteration|ja|go-}} for Sino-Japanese nouns. A few examples are given in the following table. In a few cases, there is suppletion, as with the first of the examples given below, '飯(meal/rice)'. (Note that while these prefixes are almost always written in hiragana as {{nihongo||お〜|o-}} or {{nihongo||ご〜|go-}}, the {{lang|ja|御}} kanji represents both {{transliteration|ja|o}} and {{transliteration|ja|go}} in formal writing.)

Lacking number, Japanese does not differentiate between count and mass nouns. A small number of nouns have collectives formed by reduplication (possibly accompanied by voicing and related processes (rendaku)); for example: {{nihongo3|'person'|人|hito}} and {{nihongo3|'people'|人々|hitobito}}. Reduplication is not productive. Words in Japanese referring to more than one of something are collectives, not plurals. {{transliteration|ja|Hitobito}}, for example, means "a lot of people" or "people in general"; it is never used to mean "two people". A phrase like {{transliteration|ja|edo no hitobito}} would be taken to mean "the people of Edo", or "the population of Edo", not "two people from Edo" or even "a few people from Edo". Similarly, {{transliteration|ja|yamayama}} means "many mountains".

A limited number of nouns have collective forms that refer to groups of people. Examples include {{nihongo3|'we'|私たち|watashi-tachi}}; {{nihongo3|'you' [plural]|あなたたち|anata-tachi}}; {{nihongo3|'we' (less formal, more masculine)|僕ら|bokura}}. One uncommon personal noun, {{nihongo3|'I', or in some cases, 'you'|我|ware}}, has a much more common reduplicative collective form: {{nihongo3|'we'|我々|wareware}}.

The suffixes {{nihongo3||達|-tachi}} and {{nihongo3||等|-ra}} are by far the most common collectivizing suffixes. These are, again, not pluralizing suffixes: {{transliteration|ja|tarō-tachi}} does not mean "some number of people named Taro", but instead indicates the group including Taro. Depending on context, {{transliteration|ja|tarō-tachi}} might be translated into "Taro and his friends", "Taro and his siblings", "Taro and his family", or any other logical grouping that has Taro as the representative. Some words with collectives have become fixed phrases and (commonly) refer to one person. Specifically, {{nihongo3|'child'|子供|kodomo}} and {{nihongo3|'friend'|友達|tomodachi}} can be singular, even though {{transliteration|ja|-[t]omo}} and {{transliteration|ja|-[t]achi}} were originally collectivizing in these words; to unambiguously refer to groups of them, an additional collectivizing suffix is added: {{nihongo3|'children'|子供たち|kodomo-tachi}} and {{nihongo3|'friends'|友達たち|tomodachi-tachi}}, though {{transliteration|ja|tomodachi-tachi}} is somewhat uncommon. {{transliteration|ja|Tachi}} is sometimes applied to inanimate objects, {{nihongo3|'car'|車|kuruma}} and {{nihongo3|'cars'|車たち|kuruma-tachi}}, for example, but this usage is colloquial and indicates a high level of anthropomorphisation and childlikeness, and is not more generally accepted as standard.

Grammatical cases in Japanese are marked by particles placed after the nouns.{{cite book |last=Takahashi|first=Tarō|title=Nihongo no Bunpō|script-title=ja:日本語の文法|trans-title=A Japanese Grammar |year=2010|publisher=Hituzi Syobo Publishing|location=Japan |isbn=978-4-89476-244-2|page=27|display-authors=etal|language=ja |edition=4th}} A distinctive feature of Japanese is the presence of two cases which are roughly equivalent to the nominative case in other languages: one representing the sentence topic, other representing the subject. The most important case markers are the following:

• Nominative – {{nihongo||が|ga}} for subject, {{nihongo||は|wa}} for the topic
• Genitive – {{nihongo||の|no}}
• Dative – {{nihongo||に|ni}}
• Accusative – {{nihongo||を|o}}
• Lative – {{nihongo||へ|e}}, used for destination direction (like in "to some place")
• Ablative – {{nihongo||から|kara}}, used for source direction (like in "from some place")
• Instrumental/Locative – {{nihongo||で|de}}

{{Main|Japanese pronouns}}

Although many grammars and textbooks mention {{nihongo|pronouns|代名詞|daimeishi}}, Japanese lacks true pronouns. ({{transliteration|ja|Daimeishi}} can be considered a subset of nouns.) Strictly speaking, linguistic pronouns do not take modifiers{{Citation needed|date=September 2019}}, but Japanese {{transliteration|ja|daimeishi}} do. For example, {{nihongo3|lit. "tall he"|背の高い彼|se no takai kare}} is valid in Japanese. Also, unlike true pronouns, Japanese {{transliteration|ja|daimeishi}} are not closed-class; new {{transliteration|ja|daimeishi}} are introduced and old ones go out of use relatively quickly.

A large number of {{transliteration|ja|daimeishi}} referring to people are translated as pronouns in their most common uses. Examples: {{nihongo3|he|彼|kare}}; {{nihongo3|she|彼女|kanojo}}; {{nihongo3|I|私|watashi}}; see also the adjoining table or a longer list.[http://www.sljfaq.org/afaq/pronoun.html "What are the personal pronouns of Japanese?"] in sci.lang.japan Frequently Asked Questions Some of these "personal nouns" such as {{nihongo3|I (exceedingly humble)|己|onore}}, or {{nihongo3|I (young male)|僕|boku}}, also have second-person uses: {{nihongo||おのれ|onore}} in second-person is an extremely rude "you", and {{transliteration|ja|boku}} in second-person is a diminutive "you" used for young boys. {{transliteration|ja|Kare}} and {{transliteration|ja|kanojo}} also mean "boyfriend" and "girlfriend" respectively, and this usage of the words is possibly more common than the use as pronouns.

Like other subjects, personal {{transliteration|ja|daimeishi}} are seldom used and are de-emphasized in Japanese. This is partly because Japanese sentences do not always require explicit subjects, and partly because names or titles are often used where pronouns would appear in a translation:

{{fs interlinear|indent=3|lang=ja

|「木下さん は、 背 が 高い です ね。」

|"Kinoshita-san wa, se ga takai desu ne."

|(addressing Mr. Kinoshita) "You're pretty tall, aren't you?"}}

{{fs interlinear|indent=3|lang=ja

|「専務、 明日 福岡市 西区 の 山本商事 の 社長 に 会って いただけます か？」

|"Senmu, asu Fukuoka-shi nishi-ku no Yamamoto-shōji no shachō ni atte itadakemasu ka?"

|(addressing the managing director) "Would it be possible for you to meet the president of Yamamoto Trading Co. in West Ward, Fukuoka tomorrow?"}}

The possible referents of {{transliteration|ja|daimeishi}} are sometimes constrained depending on the order of occurrence. The following pair of examples from Bart MathiasBart Mathias. [http://groups-beta.google.com/group/sci.lang.japan/msg/fed63fa6c3614895?dmode=source Discussion of pronoun reference constraints] on sci.lang.japan. illustrates one such constraint.

{{fs interlinear|indent=3|lang=ja

|本田君 に 会って、 彼 の 本 を 返した。

|Honda-kun ni atte, kare no hon o kaeshita

|(I) met Honda and returned his book. ("His" here can refer to Honda.)}}

{{fs interlinear|indent=3|lang=ja

|彼 に 会って、 本田君 の 本 を 返した。

|Kare ni atte, Honda-kun no hon o kaeshita

|(I) met him and returned Honda's book. (Here, "him" cannot refer to Honda.)}}

English has a reflexive form of each personal pronoun (himself, herself, itself, themselves, etc.); Japanese, in contrast, has one main reflexive {{transliteration|ja|daimeishi}}, namely {{nihongo3||自分|jibun}}, which can also mean 'I'. The uses of the reflexive (pro)nouns in the two languages are very different, as demonstrated by the following literal translations (*=impossible, ??=ambiguous):

If the sentence has more than one grammatical or semantic subject, then the target of {{transliteration|ja|jibun}} is the subject of the primary or most prominent action; thus in the following sentence {{transliteration|ja|jibun}} refers unambiguously to Shizuko (even though Makoto is the grammatical subject) because the primary action is Shizuko's reading.{{Verify source|date=October 2021}}

{{fs interlinear|indent=3|lang=ja

|誠 は 静子 に 自分 の 家 で 本 を 読ませた。

|Makoto wa Shizuko ni jibun no uchi de hon o yomaseta.

|Makoto made Shizuko read book(s) in her house.}}

In practice the main action is not always discernible, in which case such sentences are ambiguous. The use of {{transliteration|ja|jibun}} in complex sentences follows non-trivial rules.

There are also equivalents to {{transliteration|ja|jibun}} such as {{transliteration|ja|mizukara}}. Other uses of the reflexive pronoun in English are covered by adverbs like {{transliteration|ja|hitorideni}} which is used in the sense of "by oneself". For example,

{{fs interlinear|indent=3|lang=ja

|機械 が ひとりでに 動き出した。

|kikai ga hitorideni ugokidashita.

|The machine started operating by itself.}}

Change in a verb's valency is not accomplished by use of reflexive pronouns (in this Japanese is like English but unlike many other European languages). Instead, separate (but usually related) intransitive verbs and transitive verbs are used. There is no longer any productive morphology to derive transitive verbs from intransitive ones, or vice versa.{{clarify|date=March 2020}}

Demonstratives occur in the {{transliteration|ja|ko-}}, {{transliteration|ja|so-}}, and {{transliteration|ja|a-}} series. The {{transliteration|ja|ko-}} (proximal) series refers to things closer to the speaker than the hearer, the {{transliteration|ja|so-}} (medial) series for things closer to the hearer, and the {{transliteration|ja|a-}} (distal) series for things distant to both the speaker and the hearer. With {{transliteration|ja|do-}}, demonstratives turn into the corresponding interrogative form. Demonstratives can also be used to refer to people, for example

{{fs interlinear|indent=3|lang=ja

|「こちら は 林さん です。」

|"Kochira wa Hayashi-san desu."

|"This is Mr. Hayashi."}}

Demonstratives limit, and therefore precede, nouns; thus {{nihongo||この本|kono hon}} for "this/my book", and {{nihongo||その本|sono hon}} for "that/your book".

When demonstratives are used to refer to things not visible to the speaker or the hearer, or to (abstract) concepts, they fulfill a related but different anaphoric role. The anaphoric distals are used for shared information between the speaker and the listener.

{{fs interlinear|indent=3|lang=ja

|A： 先日、 札幌 に 行って 来ました。

|A: Senjitsu, Sapporo ni itte kimashita.

|A: I visited Sapporo recently.}}

{{fs interlinear|indent=3|lang=ja

|B： あそこ （＊そこ） は いつ 行って も いい 所 です ね。

|B: Asoko (*Soko) wa itsu itte mo ii tokoro desu ne.

|B: Yeah, that's a great place to visit whenever you go.}}

{{transliteration|ja|Soko}} instead of {{transliteration|ja|asoko}} would imply that B does not share this knowledge about Sapporo, which is inconsistent with the meaning of the sentence. The anaphoric medials are used to refer to experience or knowledge that is not shared between the speaker and listener.

{{fs interlinear|indent=3|lang=ja

|佐藤： 田中 と いう 人 が 昨日 死んだ ん だ って。

|Satō: Tanaka to iu hito ga kinō shinda n da tte...

|Sato: I heard that a man called Tanaka died yesterday...}}

{{fs interlinear|indent=3|lang=ja

|森： えっ、 本当？

|Mori: E', hontō?

|Mori: Oh, really?}}

{{fs interlinear|indent=3|lang=ja

|佐藤： だから、 その （＊あの） 人、 森さん の 昔 の 隣人 じゃ なかった っけ？

|Satō: Dakara, sono (*ano) hito, Mori-san no mukashi no rinjin ja nakatta kke?

|Sato: It's why I asked... wasn't he an old neighbour of yours?}}

Again, {{transliteration|ja|ano}} is inappropriate here because Sato does not (did not) know Tanaka personally. The proximal demonstratives do not have clear anaphoric uses. They can be used in situations where the distal series sound too disconnected:

{{fs interlinear|indent=3|lang=ja

|一体 何 です か、 これ （＊あれ） は

|Ittai nan desu ka, kore (*are) wa?

|What on earth is this?}}

Conjugative suffixes and auxiliary verbs are attached to the stem forms of the affixee. In modern Japanese, there are six stem forms, ordered following from the {{transliteration|ja|-a, -i, -u, -e, -o}} endings that these forms have in {{nihongo|5-row|五段}} verbs (according to the {{lang|ja|あ、い、う、え、お}} collation order of Japanese), where terminal and attributive forms are the same for verbs (hence only 5 surface forms), but differ for nominals, notably {{transliteration|ja|na}}-nominals.

; {{nihongo|Irrealis form|未然形|mizenkei}} {{transliteration|ja|-a}} (and {{transliteration|ja|-ō}}): is used for plain negative (of verbs), causative and passive constructions. The most common use of this form is with the {{transliteration|ja|-nai}} auxiliary that turns verbs into their negative (predicate) form. (See Verbs below.) The {{transliteration|ja|-ō}} version is used for volitional expression and formed by a {{nihongo|euphonic change|音便|onbin}}.

; {{nihongo|Continuative form|連用形|ren'yōkei}} {{transliteration|ja|-i}}: is used in a linking role (a kind of serial verb construction). This is the most productive stem form, taking on a variety of endings and auxiliaries, and can even occur independently in a sense similar to the {{transliteration|ja|-te}} ending. This form is also used to negate adjectives.

; {{nihongo|Terminal form|終止形|shūshikei}} {{transliteration|ja|-u}}: is used at the ends of clauses in predicate positions. This form is also variously known as {{nihongo|plain form|基本形|kihonkei}} or {{nihongo|dictionary form|辞書形|jishokei}} – it is the form that verbs are listed under in a dictionary.

; {{nihongo|Attributive verb#Japanese|{{vanchor|連体形}}|rentaikei}} {{transliteration|ja|-u}}: is prefixed to nominals and is used to define or classify the noun, similar to a relative clause in English. In modern Japanese it is practically identical to the terminal form, except that verbs are generally not inflected for politeness; in old Japanese these forms differed. Further, {{transliteration|ja|na}}-nominals behave differently in terminal and attributive positions; see Adjectival verbs and nouns, below.

; {{nihongo|Hypothetical form|仮定形|kateikei}} {{transliteration|ja|-e}}: is used for conditional and subjunctive forms, using the {{transliteration|ja|-ba}} ending.

; {{nihongo|Imperative form|命令形|meireikei}} {{transliteration|ja|-e}}: is used to turn verbs into commands. Adjectives do not have an imperative stem form.

The application of conjugative suffixes to stem forms follow certain {{nihongo|euphonic principles|音便|onbin}}.

{{Main|Japanese verb conjugation}}

{{nihongo|Verbs|動詞|dōshi}} in Japanese are rigidly constrained to the end of a clause. This means that the predicate position is always located at the end of a sentence.

{{fs interlinear|lang=ja|indent=3|glossing=no abbr

|猫 は 魚 を 食べる

|Neko wa sakana o taberu

|Cat TOPIC fish OBJECT eat

|"A cat eats fish"}}

The subject and objects of the verb are indicated by means of particles, and the grammatical functions of the verb (primarily tense and voice) are indicated by means of conjugation. When the subject and the dissertative topic coincide, the subject is often omitted; if the verb is intransitive, the entire sentence may consist of a single verb. Verbs have two tenses indicated by conjugation, past and non-past. The semantic difference between present and future is not indicated by means of conjugation. Usually there is no ambiguity as context makes it clear whether the speaker is referring to the present or future. Voice and aspect are also indicated by means of conjugation, and possibly agglutinating auxiliary verbs. For example, the continuative aspect is formed by means of the continuative conjugation known as the gerundive or te form of Japanese verb, and the auxiliary verb {{nihongo3|"to be"||iru}}; to illustrate, {{nihongo3|"to see"|見る|miru}} → {{nihongo3|"to be seeing"|見ている|mite iru}}.

Verbs can be semantically classified based on certain conjugations.

; Stative verbs: indicate existential properties, such as {{nihongo|"to be"|いる|iru}}, {{nihongo|"to be able to do"|出来る|dekiru}}, {{nihongo|"to need"|要る|iru}}, etc. These verbs generally do not have a continuative conjugation with {{transliteration|ja|-iru}} because they are semantically continuative already.

; Continual verbs: conjugate with the auxiliary {{transliteration|ja|-iru}} to indicate the progressive aspect. Examples: {{nihongo|"to eat"|食べる|taberu}}, {{nihongo|"to drink"|飲む|nomu}}, {{nihongo|"to think"|考える|kangaeru}}. To illustrate the conjugation, {{nihongo3|"to eat"|食べる|taberu}} → {{nihongo3|"to be eating"|食べている|tabete iru}}.

; Punctual verbs: conjugate with {{transliteration|ja|-iru}} to indicate a repeated action, or a continuing state after some action. Example: {{nihongo3|"to know"|知る|shiru}} → {{nihongo3|"to be knowing"|知っている|shitte iru}}; {{nihongo3|"to hit"|打つ|utsu}} → {{nihongo3|"to be hitting (repeatedly)"|打っている|utte iru}}.

; Non-volitional verb: indicate uncontrollable action or emotion. These verbs generally have no volitional, imperative or potential conjugation. Examples: {{nihongo3|"to like / to prefer" [emotive]|好む|konomu}}, {{nihongo3|"to be visible" [non-emotive]|見える|mieru}}.

; Movement verbs: indicate motion. Examples: {{nihongo3|"to walk"|歩く|aruku}}, {{nihongo3|"to return"|帰る|kaeru}}. In the continuative form (see § Verbal adverbs) they take the particle {{transliteration|ja|ni}} to indicate a purpose.

There are other possible classes, and a large amount of overlap between the classes.

Lexically, nearly every verb in Japanese is a member of exactly one of the following three regular conjugation groups (see also Japanese godan and ichidan verbs).

; {{nihongo|Group 2a|上一段|kami ichidan|lit. upper 1-row}}: verbs with a stem ending in {{transliteration|ja|-i}}. The terminal stem form always rhymes with {{transliteration|ja|-iru}}. Examples: {{nihongo3|"to see"|見る|miru}}, {{nihongo3|"to wear"|着る|kiru}}.

; {{nihongo|Group 2b|下一段|shimo ichidan|lit. lower 1-row}}: verbs with a stem ending in {{transliteration|ja|-e}}. The terminal stem form always rhymes with {{transliteration|ja|-eru}}. Examples: {{nihongo3|"to eat"|食べる|taberu}}, {{nihongo3|"to give" (to someone of lower or more intimate status)|くれる|kureru}}. (Some Group 1 verbs resemble Group 2b verbs, but their stems end in {{transliteration|ja|r-}}, not {{transliteration|ja|-e}}.)

; {{nihongo|Group 1|五段|godan|lit. 5-row}}: verbs with a stem ending in a consonant. When this is {{transliteration|ja|r-}} and the verb ends in {{transliteration|ja|-eru}}, it is not apparent from the terminal form whether the verb is Group 1 or Group 2b, e.g. {{nihongo3|"to return"|帰る|kaeru}}. If the stem ends in {{transliteration|ja|w-}}, that consonant sound only appears in before the final {{transliteration|ja|-a}} of the irrealis form.

The "row" in the above classification means a row in the gojūon table. "Upper 1-row" means the row that is one row above the center row (the {{transliteration|ja|u}}-row) i.e. i-row. "Lower 1-row" means the row that is one row below the center row (the {{transliteration|ja|u}}-row) i.e. {{transliteration|ja|e}}-row. "5-row" means the conjugation runs through all 5 rows of the gojūon table. A conjugation is fully described by identifying both the row and the column in the gojūon table. For example, {{nihongo3|"to see"|見る|miru}} belongs to {{nihongo3|{{transliteration|ja|ma}}-column {{transliteration|ja|i}}-row conjugation|マ行上一段活用}}, {{nihongo3|"to eat"|食べる|taberu}} belongs to {{nihongo3|{{transliteration|ja|ba}}-column {{transliteration|ja|e}}-row conjugation|バ行下一段活用}}, and {{nihongo3|"to return"|帰る|kaeru}} belongs to {{nihongo3|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}.

One should avoid confusing verbs in {{nihongo3|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}} with verbs in {{nihongo3|{{transliteration|ja|i}}-row conjugation|上一段活用}} or {{nihongo|{{transliteration|ja|e}}-row conjugation|下一段活用}}. For example, {{nihongo3|"to cut"|切る|kiru}} belongs to {{nihongo|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}, whereas its homophone {{nihongo3|"to wear"|着る|kiru}} belongs to {{nihongo|{{transliteration|ja|ka}}-column {{transliteration|ja|i}}-row conjugation|カ行上一段活用}}. Likewise, {{nihongo3|"to knead"|練る|neru}} belongs to {{nihongo|{{transliteration|ja|ra}}-column 5-row conjugation|ラ行五段活用}}, whereas its homophone {{nihongo3|"to sleep"|寝る|neru}} belongs to {{nihongo|{{transliteration|ja|na}}-column {{transliteration|ja|e}}-row conjugation|ナ行下一段活用}}.

Historically, Classical Japanese had {{nihongo|upper and lower 1-row groups|上・下一段|kami/shimo ichidan}}, {{nihongo|upper and lower 2-row groups|上・下二段|kami/shimo nidan}} and a {{nihongo|4-row group|四段|yodan}}. The {{transliteration|ja|nidan}} verbs became most of the {{transliteration|ja|ichidan}} verbs in modern Japanese (only a handful of {{transliteration|ja|kami ichidan}} verbs and a single {{transliteration|ja|shimo ichidan}} verb existed in classical Japanese). The {{transliteration|ja|yodan}} group was reclassified as the {{transliteration|ja|godan}} group during the post-WWII writing reform in 1946, to write Japanese as it is pronounced. Since verbs have migrated across groups in the history of the language, the conjugation of classical verbs cannot be ascertained from knowledge of modern Japanese alone.

Of the irregular classes, there are two:

; {{transliteration|ja|sa}}-group: which has only one member, {{nihongo3|"to do"|する|suru}}. In Japanese grammars these words are classified as {{nihongo3||サ変|sa-hen}}, an abbreviation of {{nihongo3||サ行変格活用|sa-gyō henkaku katsuyō}}, sa-row irregular conjugation).

; {{transliteration|ja|ka}}-group: which also has one member, {{nihongo3|"to come"|来る|kuru}}. The Japanese name for this class is {{nihongo3||カ行変格活用|ka-gyō henkaku katsuyō}} or simply {{nihongo3||カ変|ka-hen}}.

Classical Japanese had two further irregular classes, the {{transliteration|ja|na}}-group, which contained {{nihongo3|"to die"|死ぬ|shinu}} and {{nihongo3|"to go"/"to die"|往ぬ|inu}}, the {{transliteration|ja|ra}}-group, which included such verbs as {{nihongo3||あり|ari}}, the equivalent of modern {{transliteration|ja|aru}}, as well as quite a number of extremely irregular verbs that cannot be classified.

The following table illustrates the stem forms of the above conjugation groups, with the root indicated with dots. For example, to find the hypothetical form of the group 1 verb {{nihongo3||書く|kaku}}, look in the second row to find its root, {{transliteration|ja|kak-}}, then in the hypothetical row to get the ending {{transliteration|ja|-e}}, giving the stem form {{transliteration|ja|kake}}. When there are multiple possibilities, they are listed in the order of increasing rarity.

1. The {{transliteration|ja|-a}} and {{transliteration|ja|-o}} irrealis forms for Group 1 verbs were historically one, but since the post-WWII spelling reforms they have been written differently. In modern Japanese the {{transliteration|ja|-o}} form is used only for the volitional mood and the {{transliteration|ja|-a}} form is used in all other cases; see also the conjugation table below.
2. The unexpected ending is due to the verb's root being {{transliteration|ja|tsukaw-}} but {{transliteration|ja|w-}} only being pronounced before {{transliteration|ja|-a}} in modern Japanese.

The above are only the stem forms of the verbs; to these one must add various verb endings in order to get the fully conjugated verb. The following table lists the most common conjugations. Note that in some cases the form is different depending on the conjugation group of the verb. See Japanese verb conjugations for a full list.

1. This is an entirely different verb; {{nihongo||する|suru}} has no potential form.
2. These forms change depending on the final syllable of the verb's dictionary form (whether {{transliteration|ja|u, ku, gu, su,}} etc.). For details, see Euphonic changes, below, and the article Japanese verb conjugation.

The polite ending {{transliteration|ja|-masu}} conjugates as a group 1 verb, except that the negative imperfective and perfective forms are {{transliteration|ja|-masen}} and {{transliteration|ja|-masen deshita}} respectively, and certain conjugations are in practice rarely if ever used. The passive and potential endings {{transliteration|ja|-reru}} and {{transliteration|ja|-rareru}}, and the causative endings {{transliteration|ja|-seru}} and {{transliteration|ja|-saseru}} all conjugate as group 2b verbs. Multiple verbal endings can therefore agglutinate. For example, a common formation is the causative-passive ending: {{transliteration|ja|-sase-rareru}}.

{{fs interlinear|lang=ja|indent=3

|僕 は 姉 に 納豆 を 食べさせられた。

|Boku wa ane ni nattō o tabesaserareta.

|I was made to eat {{transliteration|ja|nattō}} by my (elder) sister.}}

As should be expected, the vast majority of theoretically possible combinations of conjugative endings are not semantically meaningful.

Japanese has a large variety of related pairs of transitive verbs (that take a direct object) and intransitive verbs (that do not usually take a direct object), such as the transitive {{nihongo3|someone or something begins an activity|始める|hajimeru}}, and the intransitive {{nihongo3|an activity begins|始まる|hajimaru}}.[http://www.sljfaq.org/afaq/jitadoushi.html "What's the difference between hajimeru and hajimaru?"] in sci.lang.japan Frequently Asked QuestionsKim Allen (2000) [http://kimallen.sheepdogdesign.net/Japanese/verbs2.html "Japanese verbs, part 2"] {{Webarchive|url=https://web.archive.org/web/20070810194203/http://kimallen.sheepdogdesign.net/Japanese/verbs2.html |date=2007-08-10}} in Japanese for the Western Brain

Note: Some intransitive verbs (usually verbs of motion) take what looks like a direct object, but is not.{{cite web |title=対応する他動詞のある自動詞の意味的・統合的特徴 |url=http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/8792/1/gen00006_079.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/8792/1/gen00006_079.pdf |archive-date=2022-10-09 |url-status=live |publisher=Kyoto University |access-date=May 18, 2013}}{{dead link |date=April 2017 |bot=InternetArchiveBot |fix-attempted=yes}} For example, {{nihongo3|to leave|離れる|hanareru}}:

{{fs interlinear|lang=ja|indent=3

|私 は 東京 を 離れる。

|Watashi wa Tōkyō o hanareru.

|I leave Tokyo.}}

{{anchor|Adjectives|adjectives}}

{{Main|Japanese adjectives}}

Semantically speaking, words that denote attributes or properties are primarily distributed between two morphological classes (there are also a few other classes):

• {{nihongo|adjectival verbs|形容詞|keiyōshi|conventionally called "{{transliteration|ja|i}}-adjectives"}}– these have roots and conjugating stem forms, and are semantically and morphologically similar to stative verbs.
• {{nihongo|adjectival nouns|形容動詞|keiyōdōshi|lit. "adjectival verb", conventionally called "{{transliteration|ja|na}}-adjectives"}}– these are nouns that combine with the copula.

Unlike adjectives in languages like English, {{transliteration|ja|i}}-adjectives in Japanese inflect for aspect and mood, like verbs. Japanese adjectives do not have comparative or superlative inflections; comparatives and superlatives have to be marked periphrastically using adverbs like {{nihongo3|'more'||motto}} and {{nihongo3|'most'||ichiban}}.

Every adjective in Japanese can be used in an attributive position, and nearly every Japanese adjective can be used in a predicative position. There are a few Japanese adjectives that cannot predicate, known as {{nihongo3|attributives|連体詞|rentaishi}}, which are derived from other word classes; examples include {{nihongo3|"big"|大きな|ōkina}}, {{nihongo3|"small"|小さな|chiisana}}, and {{nihongo3|"strange"|おかしな|okashina}} which are all stylistic {{transliteration|ja|na}}-type variants of normal {{transliteration|ja|i}}-type adjectives.

All {{transliteration|ja|i}}-adjectives except for {{nihongo3|good|いい|ii}} have regular conjugations, and {{transliteration|ja|ii}} is irregular only in the fact that it is a changed form of the regular adjective {{nihongo3||良い|yoi}} permissible in the terminal and attributive forms. For all other forms it reverts to {{transliteration|ja|yoi}}.

1. The attributive and terminal forms were formerly {{nihongo||安き|.ki}} and {{nihongo||安し|.shi}}, respectively; in modern Japanese these are used productively for stylistic reasons only, although many set phrases such as {{nihongo3|anonymous|名無し|nanashi}} and {{nihongo3|[general positive interjection]|よし|yoshi|sometimes written {{transliteration|ja|yosh}}}}, derive from them.
2. The imperative form is extremely rare in modern Japanese, restricted to set patterns like {{nihongo3|'sooner or later'|遅かれ早かれ|osokare hayakare}}, where they are treated as adverbial phrases. It is impossible for an imperative form to be in a predicate position.

Common conjugations of adjectives are enumerated below. {{transliteration|ja|ii}} is not treated separately, because all conjugation forms are identical to those of {{transliteration|ja|yoi}}.

1. Note that these are just forms of the {{transliteration|ja|i}}-type adjective {{nihongo||ない|nai}}
2. Since most adjectives describe non-volitional conditions, the volitional form is interpreted as "it is possible", if sensible. In some rare cases it is semi-volitional: {{nihongo3|'OK'|良かろう|yokarō|lit: "let it be good"}} in response to a report or request.

Adjectives too are governed by euphonic rules in certain cases, as noted in the section on it below. For the polite negatives of {{transliteration|ja|na}}-type adjectives, see also the section below on the copula {{nihongo||だ|da}}.

The copula {{transliteration|ja|da}} behaves very much like a verb or an adjective in terms of conjugation.

Note that there are no potential, causative, or passive forms of the copula, just as with adjectives.

The following are some examples.

{{blockquote|{{lang|ja|ジョンは学生だ。}}

{{transliteration|ja|JON wa gakusei da}}

"John is a student."}}

{{blockquote|{{lang|ja|明日も晴れなら、ピクニックしよう。}}

{{transliteration|ja|Ashita mo hare nara, PIKUNIKKU shiyō}}

"If tomorrow is clear too, let's have a picnic."}}

In continuative conjugations, {{nihongo||では|de wa}} is often contracted in speech to {{nihongo||じゃ|ja}}; for some kinds of informal speech {{transliteration|ja|ja}} is preferable to {{transliteration|ja|de wa}}, or is the only possibility.

{{Clear}}

{{Main|Onbin}}

Modern pronunciation is a result of a long history of phonemic drift that can be traced back to written records of the 13th century, and possibly earlier. However, it was only in 1946 that the Japanese ministry of education modified existing kana usage to conform to the {{nihongo|standard dialect|共通語|kyōtsūgo}}. All earlier texts used the archaic orthography, now referred to as historical kana usage. The adjoining table is a nearly exhaustive list of these spelling changes.

Note that the palatalized morae {{lang|ja|ゆ}} and {{lang|ja|よ}} ({{transliteration|ja|yu}} and {{transliteration|ja|yo}}) combine with the initial consonant (if present) yielding a palatalized syllable. The most basic example of this is modern {{Nihongo3|today|今日（きょう）|kyō}}, which historically developed as {{Nihongo3||けふ|kefu}} → {{Nihongo3||きょう|kyō}}, via the {{Nihongo3||えふ|efu}} → {{Nihongo3||よう|yō}} rule.

A few sound changes are not reflected in the spelling. Firstly, {{transliteration|ja|ou}} merged with {{transliteration|ja|oo}}, both being pronounced as a long {{transliteration|ja|ō}}. Secondly, the particles {{lang|ja|は}} and {{lang|ja|を}} are still written using historical kana usage, though these are pronounced as {{transliteration|ja|wa}} and {{transliteration|ja|o}} respectively, rather than {{transliteration|ja|ha}} and {{transliteration|ja|wo}}.

Among Japanese speakers, it is not generally understood that the historical kana spellings were, at one point, reflective of pronunciation.{{Citation needed|date=November 2022}} For example, the modern {{transliteration|ja|on'yomi}} reading {{Nihongo3||よう|yō}} (for {{Nihongo|leaf|葉|yō}}) arose from the historical {{Nihongo3||えふ|efu}}. The latter was pronounced something like {{IPA|[ʲepu]}} by the Japanese at the time it was borrowed (compare Middle Chinese {{IPA|[jiɛp̚]}}). However, a modern reader of a classical text would still read this as {{IPAc-ja|yō}}, the modern pronunciation.

{{Main|Japanese verb conjugation}}

Conjugations of some verbs and adjectives differ from the prescribed formation rules because of euphonic changes. Nearly all of these euphonic changes are themselves regular. For verbs the exceptions are all in the ending of the continuative form of group when the following auxiliary starts with a {{transliteration|ja|t}}-sound (i.e. {{nihongo||-た|-ta}}, {{nihongo||-て|-te}}, {{nihongo||-たり|-tari}}, etc.).

{{clear}}

* denotes impossible/ungrammatical form.

There is one other irregular change: {{nihongo3|to go|行く|iku}}, for which there is an exceptional continuative form: {{nihongo||行き|iki}} + {{nihongo||て|te}} → {{nihongo||行って|itte}}, {{nihongo||行き|iki}} + {{nihongo||た|ta}} → {{nihongo||行った|itta}}, etc.

There are dialectical differences, which are also regular and generally occur in similar situations. For example, in Kansai dialect the {{transliteration|ja|-i}} + {{transliteration|ja|t-}} conjugations are instead changed to {{transliteration|ja|-ut-}} (u-onbin), as in {{Nihongo3||思うた|omōta}} instead of {{Nihongo3||思った|omotta}}, as perfective of {{Nihongo3|think|思う|omou}}. In this example, this can combine with the preceding vowel via historical sound changes, as in {{Nihongo3||しもうた|shimōta}} ({{transliteration|ja|au}} → {{transliteration|ja|ō}}) instead of standard {{Nihongo3||しまった|shimatta}}.

The continuative form of proper adjectives, when followed by polite forms such as {{Nihongo3|be|ござる/御座る|gozaru}} or {{Nihongo3|know, think|存じる|zonjiru}}, undergoes a transformation; this may be followed by historical sound changes, yielding a one-step or two-step sound change. Note that these verbs are almost invariably conjugated to polite {{Nihongo3||〜ます|-masu}} form, as {{Nihongo3||ございます|gozaimasu}} and {{Nihongo3||存じます|zonjimasu}} (note the irregular conjugation of {{transliteration|ja|gozaru}}, discussed below), and that these verbs are preceded by the continuative form – {{Nihongo3||〜く|-ku}} – of adjectives, rather than the terminal form – {{Nihongo3||〜い|-i}} – which is used before the more everyday {{Nihongo3|be|です|desu}}.

The rule is {{Nihongo3||〜く|-ku}} → {{Nihongo3||〜う|-u}} (dropping the {{transliteration|ja|-k-}}), possibly also combining with the previous syllable according to the spelling reform chart, which may also undergo palatalization in the case of {{Nihongo3||ゆ、よ|yu, yo}}.

Historically there were two classes of proper Old Japanese adjectives, {{Nihongo3||〜く|-ku}} and {{Nihongo3||〜しく|-shiku}} ("{{transliteration|ja|-ku}} adjective" means "not preceded by {{transliteration|ja|shi}}"). This distinction collapsed during the evolution of Late Middle Japanese adjectives, and both are now considered {{Nihongo3||〜い|-i}} adjectives. The sound change for {{transliteration|ja|-shii}} adjectives follows the same rule as for other {{transliteration|ja|-ii}} adjectives, notably that the preceding vowel also changes and the preceding mora undergoes palatalization, yielding {{Nihongo3||〜しく|-shiku}} → {{Nihongo3||〜しゅう|-shū}}, though historically this was considered a separate but parallel rule.

Respectful verbs such as {{nihongo3|'to get'|くださる|kudasaru}}, {{nihongo3|'to do'|なさる|nasaru}}, {{nihongo3|'to be'|ござる|gozaru}}, {{nihongo3|'to be/come/go'|いらっしゃる|irassharu}}, {{nihongo3|'to say'|おっしゃる|ossharu}}, etc. behave like group 1 verbs, except in the continuative and imperative forms.

In speech, common combinations of conjugation and auxiliary verbs are contracted in a fairly regular manner.

There are occasional others, such as {{transliteration|ja|-aranai}} → {{transliteration|ja|-annai}} as in {{Nihongo3|don't understand|分からない|wakaranai}} → {{Nihongo3||分かんない|wakannai}} and {{Nihongo3|boring|つまらない|tsumaranai}} → {{Nihongo3||つまんない|tsumannai}} – these are considered quite casual and are more common among the younger generation.{{citation needed|date=November 2021}}

Contractions differ by dialect, but behave similarly to the standard ones given above. For example, in the Kansai dialect, {{Nihongo3||〜てしまう|-te shimau}} → {{Nihongo3||〜てまう|-temau}}.

Adverbs in Japanese are not as tightly integrated into the morphology as in many other languages; adverbs are not an independent class of words, but the role of an adverb is played by other words. For example, every adjective in the continuative form can be used as an adverb; thus, {{nihongo3|'weak' [adj]|弱い|yowai}} → {{nihongo3|'weakly' [adv]|弱く|yowaku}}. The primary distinguishing characteristic of adverbs is that they cannot occur in a predicate position, just as it is in English. The following classification of adverbs is not intended to be authoritative or exhaustive.

{{Anchor|Verbal adverbs}}

; Verbal adverbs: verbs in the continuative form with the particle {{transliteration|ja|ni}}. E.g. {{nihongo3|'to see'|見る|miru}} → {{nihongo3|'for the purpose of seeing'|見に|mi ni}}, used for instance as: {{nihongo3|'go to see (something)'|見に行く|mi ni iku}}.

; Adjectival adverbs: adjectives in the continuative form, as mentioned above. Example: {{nihongo3|'weak' [adj]|弱い|yowai}} → {{nihongo3|'weakly' [adv]|弱く|yowaku}}

; Nominal adverbs: grammatical nouns that function as adverbs. Example: {{nihongo3|'most highly'|一番|ichiban}}.

; Sound symbolism: words that mimic sounds or concepts. Examples: {{nihongo3|'sparklingly'|きらきら|kirakira}}, {{nihongo3|'suddenly'|ぽっくり|pokkuri}}, {{nihongo3|'smoothly' (sliding)|するする|surusuru}}, etc.

Often, especially for sound symbolism, the particle {{nihongo3|'as if'|と|to}} is used. See the article on Japanese sound symbolism.

Although called "conjunctions", conjunctions in Japanese are – as their English translations show – actually a kind of adverb:

Examples of conjunctions: {{nihongo3|'and then'|そして|soshite}}, {{nihongo3|'and then/again'|また|mata}}, etc.

Interjections in Japanese differ little in use and translation from interjections in English:

Examples of interjections: {{nihongo3|yes/OK/uh|はい|hai}}, {{nihongo3|wow!|へえ|hē}}, {{nihongo3|no/no way|いいえ|iie}}, {{nihongo3|hey!|おい|oi}}, etc.

{{Main|Japanese particles}}

Particles in Japanese are postpositional, as they immediately follow the modified component. Both the pronunciation and spelling differs for the particles {{nihongo3||は|wa}}, {{nihongo3||へ|e}} and {{nihongo3||を|o}}, and are romanized according to pronunciation rather than spelling. Only a few prominent particles are listed here.

{{see also|topic and comment}}

The complex distinction between the so-called topic, {{nihongo||は|wa}}, and subject, {{nihongo||が|ga}}, particles has been the theme of many doctoral dissertations and scholarly disputes.{{citation needed|date=November 2021}} The clause {{nihongo||象は鼻が長い|zō-wa hana-ga nagai}} is well known for appearing to contain two subjects. It does not simply mean "the elephant's nose is long", as that can be translated as {{nihongo||象の鼻は長い|zō-no hana-wa nagai}}. Rather, a more literal translation would be "(speaking of) the elephant, its nose is long"; furthermore, as Japanese does not distinguish between singular and plural the way English does, it could also mean "as for elephants, their noses are long".

Two major scholarly surveys of Japanese linguistics in English, clarify the distinction.{{sfn|Shibatani|1990b}}{{sfn|Kuno|1973}} To simplify matters, the referents of {{transliteration|ja|wa}} and {{transliteration|ja|ga}} in this section are called the topic and subject respectively, with the understanding that if either is absent, the grammatical topic and subject may coincide.

As an abstract and rough approximation, the difference between {{transliteration|ja|wa}} and {{transliteration|ja|ga}} is a matter of focus: {{transliteration|ja|wa}} gives focus to the action of the sentence, i.e., to the verb or adjective, whereas {{transliteration|ja|ga}} gives focus to the subject of the action. However, when first being introduced to the topic and subject markers {{transliteration|ja|wa}} and {{transliteration|ja|ga}}, most are told that the difference between the two is simpler. The topic marker, {{transliteration|ja|wa}}, is used to declare or to make a statement. The subject marker, {{transliteration|ja|ga}}, is used for new information, or asking for new information.

{{see also|Topic marker#Japanese: は}}

The use of {{transliteration|ja|wa}} to introduce a new theme of discourse is directly linked to the notion of grammatical theme. Opinions differ on the structure of discourse theme, though it seems fairly uncontroversial to imagine a first-in-first-out hierarchy of themes that is threaded through the discourse. However, the usage of this understanding of themes can be limiting when speaking of their scope and depth, and the introduction of later themes may cause earlier themes to expire.{{explain|date=November 2021}} In these sorts of sentences, the steadfast translation into English uses constructs like "speaking of X" or "on the topic of X", though such translations tend to be bulky as they fail to use the thematic mechanisms of English. For lack of a comprehensive strategy, many teachers of Japanese emphasize the "speaking of X" pattern without sufficient warning.

{{fs interlinear|lang=ja|indent=3

|ジョン は 学生 です。

|JON wa gakusei desu

|(On the topic of) John, (he) is a student.}}

A common linguistic joke shows the insufficiency of rote translation with the sentence {{nihongo||僕はウナギだ|boku wa unagi da}}, which per the pattern would translate as "I am an eel." (or "(As of) me is eel"). Yet, in a restaurant this sentence can reasonably be used to say "My order is eel" (or "I would like to order an eel"), with no intended humour. This is because the sentence should be literally read, "As for me, it is an eel," with "it" referring to the speaker's order. The topic of the sentence is clearly not its subject.

Related to the role of {{transliteration|ja|wa}} in introducing themes is its use in contrasting the current topic and its aspects from other possible topics and their aspects. The suggestive pattern is "X, but…" or "as for X, …".

{{fs interlinear|lang=ja|indent=3

|雨 は 降って います が…

|ame wa futte imasu ga…

|The rain is falling, but…}}

Because of its contrastive nature, the topic cannot be undefined.

{{fs interlinear|lang=ja|indent=3

|＊誰か は 本 を 読んで いる。

|*dareka wa hon o yonde iru

|*Someone is reading the book.}}

In this use, {{transliteration|ja|ga}} is required.

In practice, the distinction between thematic and contrastive {{transliteration|ja|wa}} is not that useful. There can be at most one thematic {{transliteration|ja|wa}} in a sentence, and it has to be the first {{transliteration|ja|wa}} if one exists, and the remaining {{transliteration|ja|wa}}s are contrastive. The following sentence illustrates the difference;{{sfn|Kuno|1973|p={{page needed|date=July 2024}}}}

{{fs interlinear|lang=ja|indent=3

|僕 が 知って いる 人 は 誰も 来なかった。

|boku ga shitte iru hito wa daremo konakatta

|(1) Of all the people I know, none came.

(2) (People came but), there weren't any of the people I know.}}

The first interpretation is the thematic {{transliteration|ja|wa}}, treating {{nihongo|"the people I know"||boku ga shitte iru hito}} as the theme of the predicate {{nihongo|"none came"||dare mo konakatta}}. That is, if the speaker knows A, B, ..., Z, then none of the people who came were A, B, ..., Z. The second interpretation is the contrastive {{transliteration|ja|wa}}. If the likely attendees were A, B, ..., Z, and of them the speaker knows P, Q and R, then the sentence says that P, Q and R did not come. The sentence says nothing about A', B', ..., Z', all of whom the speaker knows, but none of whom were likely to come. In practice, the first interpretation is the likely one.

Unlike {{transliteration|ja|wa}}, the subject particle {{transliteration|ja|ga}} nominates its referent as the sole satisfier of the predicate. This distinction is famously illustrated by the following pair of sentences:

{{fs interlinear|lang=ja|indent=3

|ジョンさん は 学生 です。

|Jon-san wa gakusei desu

|John is a student. (There may be other students among the people we're talking about.)}}

{{fs interlinear|lang=ja|indent=3

|(この グループ の 中 で) ジョン が 学生 です。

|(Kono gurūpu no naka de) Jon ga gakusei desu

|(Of all the people we are talking about) it is John who is the student.}}

The distinction between each example sentence may be made easier to understand if thought of in terms of the question each statement could answer. The first example sentence could answer the question:

{{fs interlinear|lang=ja|indent=3

|ジョンさん の 仕事 は 何 です か。

|Jon-san no shigoto wa nan desu ka

|What is John's occupation?}}

Whereas the second example sentence could answer the question:

{{fs interlinear|lang=ja|indent=3

|どちら の 方 が 学生 です か。

|Dochira no kata ga gakusei desu ka

|Which one (of them) is the student?}}

Similarly, in a restaurant, if asked by the waitstaff who has ordered the eels, the customer who ordered it could say:

{{fs interlinear|lang=ja|indent=3

|僕 が ウナギ だ。

|Boku ga unagi da

|The eels are for me (not these other people).}}

For certain verbs, {{transliteration|ja|ga}} is typically used instead of {{transliteration|ja|o}} to mark what would be the direct object in English:

{{fs interlinear|lang=ja|indent=3

|ジョンさん は フランス語 が 出来る。

|Jon-san wa furansu-go ga dekiru

|John knows French.}}

There are various common expressions that use verbs in English, often transitive verbs, where the action happens to a specific object: "to be able to do something", "to want something", "to like something", "to dislike something". These same ideas are expressed in Japanese using adjectives and intransitive verbs that describe a subject, instead of actions that happen to an object: {{nihongo|"to be possible"|出来る|dekiru}}, {{nihongo|"to be desired/desirable"|ほしい|hoshii}}, {{nihongo|"to be liked"|好きだ|suki da}}, {{nihongo|"to be disliked"|嫌いだ|kirai da}}. The equivalent of the English subject is instead the topic in Japanese and thus marked by {{transliteration|ja|wa}}, reflecting the topic-prominent nature of Japanese grammar.

Since these constructions in English describe an object, whereas the Japanese equivalents describe a subject marked with {{nihongo||が|ga}}, some sources call this usage of {{nihongo||が|ga}} the "objective ga". Strictly speaking, this label may be misleading, as there is no object in the Japanese constructions.

As an example, the Japanese verb {{nihongo||分かる|wakaru}} is often glossed as transitive English verb "to understand". However, wakaru is an intransitive verb that describes a subject, so a more literal gloss would be "to be understandable".

{{fs interlinear|lang=ja|indent=3

|ジョンさん は 日本語 が 分かる。

|Jon-san wa nihongo ga wakaru.

|* John understands Japanese. → translating into idiomatic English, using the transitive verb "to understand"

* As for John, Japanese is understandable. → translating more closely to the Japanese, with "Japanese" as the subject of an intransitive descriptive verb}}

The direct object of transitive verbs is indicated by the object particle {{nihongo||を|o}}.

{{fs interlinear|lang=ja|indent=3

|ジョンさん は 青い セーター を 着て いる。

|Jon-san wa aoi sētā o kite iru

|John is wearing a blue sweater.}}

This particle can also mean "through" or "along" or "out of" when used with motion verbs:

{{fs interlinear|lang=ja|indent=3

|メアリ が 細い 道 を 歩いて いた。

|MEARI ga hosoi michi o aruite ita

|Mary was walking along a narrow road.}}

{{fs interlinear|lang=ja|indent=3

|国境 の 長い トンネル を 抜ける と 雪国 で あった。

|kokkyō no nagai TONNERU o nukeru to yukiguni de atta

|(The train) came out of the long border tunnel into the snow country.}}

The general instrumental particle is {{nihongo||で|de}}, which can be translated as "using" or "by":

{{fs interlinear|lang=ja|indent=3

|肉 は ナイフ で 切る こと。

|niku wa NAIFU de kiru koto

|Meat must be cut with a knife.}}

{{fs interlinear|lang=ja|indent=3

|電車 で 行きましょう。

|densha de ikimashō

|Let's go by train.}}

This particle also has other uses: "at" (temporary location):

{{fs interlinear|lang=ja|indent=3

|町角 で 先生 に 会った。

|machikado de sensei ni atta

|(I) met my teacher at the street corner.}}

"In":

{{fs interlinear|lang=ja|indent=3

|海 で 泳ぐ の は 難しい。

|umi de oyogu no wa muzukashii

|Swimming in the sea is hard.}}

"With" or "in (the span of)":

{{fs interlinear|lang=ja|indent=3

|劇 は 主人公 の 死 で 終る。

|geki wa shujinkō no shi de owaru

|The play ends with the protagonist's death.}}

{{fs interlinear|lang=ja|indent=3

|俺 は 二秒 で 勝つ。

|ore wa nibyō de katsu

|I'll win in two seconds.}}

The general locative particle is {{nihongo||に|ni}}.

{{fs interlinear|lang=ja|indent=3

|東京 に 行きましょう。

|Tōkyō ni ikimashō

|Let's go to Tokyo.}}

In this function it is interchangeable with {{nihongo||へ|e}}. However, {{transliteration|ja|ni}} has additional uses: "at (prolonged)":

{{fs interlinear|lang=ja|indent=3

|私 は 大手町 一丁目 99 番地 に 住んで います。

|watashi wa Ōtemachi itchōme 99 banchi ni sunde imasu

|I live at Ōtemachi ichōme 99 banchi.}}

"On":

{{fs interlinear|lang=ja|indent=3

|氷 は 水 に 浮く。

|kōri wa mizu ni uku

|Ice floats on water.}}

"In (some year)", "at (some point in time)":

{{fs interlinear|lang=ja|indent=3

|春 の 夕暮れ に……

|haru no yūgure ni…

|On a spring eve…}}

To conjoin nouns, と to is used.

{{fs interlinear|lang=ja|indent=3

| かばん に は、 教科書 三冊 と 漫画本 五冊 を 入れて います。

| Kaban ni wa kyōkasho san-satsu to manga-bon go-satsu o irete imasu

| I have three textbooks and five comic books in the bag.}}

The additive particle {{nihongo||も|mo}} can be used to conjoin larger nominals and clauses.

{{fs interlinear|lang=ja|indent=3

| ヨハン は ドイツ人 だ。 ブリゲッタ も ドイツ人 だ。

| YOHAN wa DOITSU-jin da. BURIGETTA mo DOITSU-jin da

| Johann is a German. Brigitte is a German too.}}

{{fs interlinear|lang=ja|indent=3

| 彼 は 映画 スター で あり、 政治家 で も ある。

| kare wa eiga SUTĀ de ari, seijika de mo aru

| He is a movie star and also a politician.}}

For an incomplete list of conjuncts, {{nihongo||や|ya}} is used.

{{fs interlinear|lang=ja|indent=3

| ボリス や イバン を 呼べ。

| BORISU ya IBAN o yobe

| Call Boris, Ivan, etc.}}

When only one of the conjuncts is necessary, the disjunctive particle {{nihongo||か|ka}} is used.

{{fs interlinear|lang=ja|indent=3

| 寿司 か 刺身 か、 何か 注文 して ね。

| sushi ka sashimi ka, nanika chūmon shite ne

| Please order sushi or sashimi or something.}}

Quantities are listed between {{nihongo|'from'|から|kara}} and {{nihongo|'to'|まで|made}}.

{{fs interlinear|lang=ja|indent=3

| 華氏 92 度 から 96 度 まで の 熱 は 心配 する もの で は ない。

| Kashi 92 do kara 96 do made no netsu wa shinpai suru mono de wa nai

| A temperature between 92 Fahrenheit and 96 is not worrisome.}}

This pair can also be used to indicate time or space.

: {{lang|ja|朝9時(午前9時)から11時まで授業があるんだ。}}

: {{transliteration|ja|asa ku-ji kara jūichi-ji made jugyō ga aru n da}}

: You see, I have classes between 9 a.m. and 11 a.m.

Because {{transliteration|ja|kara}} indicates starting point or origin, it has a related use as "because", analogously to English "since" (in the sense of both "from" and "because"):

{{fs interlinear|lang=ja|indent=3

| スミスさん は とても 積極的 な 人 です から、 いつも 全部 頼まれて いる の かもしれません。

| SUMISU-san wa totemo sekkyokuteki na hito desu kara, itsumo zenbu tanomarete iru no kamoshiremasen

| Mr. Smith, because you're so assertive, you may always be asked to do everything.}}

The particle {{transliteration|ja|kara}} and a related particle {{transliteration|ja|yori}} are used to indicate lowest extents: prices, business hours, etc.

{{fs interlinear|lang=ja|indent=3

| 私たち の 店 は 7時 より 営業 して おります。

| Watashitachi no mise wa shichi-ji yori eigyō shite orimasu

| Our shop is open for business from 7 onwards.}}

{{transliteration|ja|Yori}} is also used in the sense of "than".

{{fs interlinear|lang=ja|indent=3

| お前 は 姉ちゃん より うるさい ん だ!

| omae wa nē-chan yori urusai n da

| You are louder/more talkative than my elder sister!}}

The particle {{nihongo||と|to}} is used to set off quotations.

{{fs interlinear|lang=ja|indent=3

|「殺して… 殺して」 と あの 子 は 言っていた。

|"koroshite… koroshite" to ano ko wa itteita

|The girl was saying, "Kill me… kill me."}}

{{fs interlinear|lang=ja|indent=3

|猫 が ニャー ニャー と 鳴く。

|neko ga NYĀ NYĀ to naku

|The cat says meow, meow.}}

It is also used to indicate a manner of similarity, "as if", "like" or "the way".

{{fs interlinear|lang=ja|indent=3

|彼 は 「愛してる よ」 と 言って、 ぽっくり と 死んだ。

|kare wa "aishiteru yo" to itte, pokkuri to shinda

|He said "I love you," and dropped dead.}}

In a related conditional use, it functions like "after/when", or "upon".

{{fs interlinear|lang=ja|indent=3

|雨 が 上がる と、 子ども達 は 授業 を 忘れて、 日 の 当たっている 水たまり の 誘惑 に 夢中 に なる。

|ame ga agaru to, kodomo-tachi wa jugyō o wasurete, hi no atatteiru mizutamari no yūwaku ni muchū ni naru

|Rain stops and then: children, forgetting their lessons, give in to the temptation of sun-faced puddles.}}

{{fs interlinear|lang=ja|indent=3

|国境 の 長い トンネル を 抜ける と 雪国 で あった。

|kokkyō no nagai TONNERU o nukeru to, yukiguni de atta

|(The train) came out of the long border tunnel (and then) into the snow country.}}

Finally it is used with verbs like {{nihongo|to meet (with)|会う|au}} or {{nihongo|to speak (with)|話す|hanasu}}.

{{fs interlinear|lang=ja|indent=3

|ジョン が メアリー と 初めて 会った の は、 1942 年 の 春 の 夕暮れ時 の こと だった。

|JON ga MEARI to hajimete atta no wa, 1942 nen no haru no yūguredoki no koto datta

|John met Mary for the first time on a dusky afternoon of spring in 1942.}}

This last use is also a function of the particle {{nihongo||に|ni}}, but {{transliteration|ja|to}} indicates reciprocation which {{transliteration|ja|ni}} does not.

: {{lang|ja|ジョンはメアリーと恋愛している。(usually say ジョンはメアリーと付き合っている。)}}

: {{transliteration|ja|JON wa MEARI[II] to ren'ai shite iru (JON wa MEARI[II] to tsukiatte iru)}}

: John and Mary are in love.

: {{lang|ja|ジョンはメアリーに恋愛している。(usually say ジョンはメアリーに恋している。)}}

: {{transliteration|ja|JON wa MEARI[II] ni ren'ai shite iru (JON wa MEARI[II] ni koi shite iru)}}

: John loves Mary (but Mary might not love John back).

Finally, the particle {{nihongo||よ|yo}} is used in a hortative or vocative sense.

{{fs interlinear|lang=ja|indent=3

|可愛い 娘 よ、 私 に 顔 を しかめるな。

|kawaii musume yo, watashi ni kao o shikameruna

|Oh my beloved daughter, don't frown at me so!}}

The sentence-final particle {{nihongo||か|ka}} turns a declarative sentence into a question.

{{fs interlinear|lang=ja|indent=3

|そちら は アメリカ人 でしょう か?

|sochira wa amerika-jin deshō ka?

|Are you perchance an American?}}

Other sentence-final particles add emotional or emphatic impact to the sentence. The particle {{nihongo||ね|ne}} softens a declarative sentence, similar to English "you know?", "eh?", "I tell you!", "isn't it?", "aren't you?", etc.

{{fs interlinear|lang=ja|indent=3

|彼 に 電話 しなかった の ね。

|kare ni denwa shinakatta no ne

|You didn't call him up, did you?}}

{{fs interlinear|lang=ja|indent=3

|近々 ロンドン に 引っ越される そう です ね。

|chikajika rondon ni hikkosareru sō desu ne.

|I hear you're moving to London soon. Is that true?}}

A final {{nihongo||よ|yo}} is used in order to soften insistence, warning or command, which would sound very strong without any final particles.

{{fs interlinear|lang=ja|indent=3

|嘘 なんか ついて ない よ！

|uso nanka tsuite nai yo!

|I'm not lying!}}

There are many such emphatic particles; some examples: {{nihongo||ぜ|ze}} and {{nihongo||ぞ|zo}} usually used by males; {{nihongo||な|na}} a less formal form of {{transliteration|ja|ne}}; {{nihongo||わ|wa}} used like {{transliteration|ja|yo}} by females (and males in the Kansai region), etc. They are essentially limited to speech or transcribed dialogue.

Compound particles are formed with at least one particle together with other words, including other particles. The commonly seen forms are:

• particle + verb (term. or cont. or {{transliteration|ja|-te}} form)
• particle + noun + particle
• noun + particle

Other structures are rarer, though possible. A few examples:

{{fs interlinear|lang=ja|indent=3

|その 件 に 関して 知っている 限り の こと を 教えて もらいたい。

|sono ken ni kan-shite shitte-iru kagiri no koto o oshiete moraitai

|Kindly tell me everything you know concerning that case. (particle + verb in cont.)}}

{{fs interlinear|lang=ja|indent=3

|外国語 を 学習 する 上 で 大切 な こと は 毎日 の 努力 が もの を 言う と いう こと で ある。

|gaikokugo o gakushū suru ue de taisetsu na koto wa mainichi no doryoku ga mono o iu to iu koto de aru

|In studying a foreign language, daily effort gives the most rewards. (noun + particle)}}

{{fs interlinear|lang=ja|indent=3

|兄 は 両親 の 心配 を よそ に、 大学 を やめて しまった。

|ani wa ryōshin no shinpai o yoso ni, daigaku o yamete shimatta

|Ignoring my parents' worries, my brother dropped out of college. (particle + noun + particle)}}

All auxiliary verbs attach to a verbal or adjectival stem form and conjugate as verbs. In modern Japanese there are two distinct classes of auxiliary verbs:

; {{nihongo|Pure auxiliaries|助動詞|jodōshi}} : are usually just called verb endings or conjugated forms. These auxiliaries do not function as independent verbs.

; {{nihongo|Helper auxiliaries|補助動詞|hojodōshi}} : are normal verbs that lose their independent meaning when used as auxiliaries.

In classical Japanese, which was more heavily agglutinating than modern Japanese, the category of auxiliary verb included every verbal ending after the stem form, and most of these endings were themselves inflected. In modern Japanese, however, some of them have stopped being productive. The prime example is the classical auxiliary {{nihongo||たり|-tari}}, whose modern forms {{nihongo||た|-ta}} and {{nihongo||て|-te}} are no longer viewed as inflections of the same suffix, and can take no further affixes.

1. {{nihongo||ます|masu}} has stem forms: irrealis {{lang|ja|ませ}} and {{lang|ja|ましょ}}, continuative {{lang|ja|まし}}, terminal {{lang|ja|ます}}, attributive {{lang|ja|ます}}, hypothetical {{lang|ja|ますれ}}, imperative {{lang|ja|ませ}}.
2. {{nihongo||られる|rareru}} in potential usage is sometimes shortened to {{nihongo||れる|reru}} (group 2); thus {{nihongo3|'to be able to eat'|食べれる|tabereru}} instead of {{nihongo3||食べられる|taberareru}}. However, it is considered non-standard.
3. {{nihongo||させる|saseru}} is sometimes shortened to {{nihongo||さす|sasu}} (group 1), but this usage is somewhat literary.

Much of the agglutinative flavour of Japanese stems from helper auxiliaries, however. The following table contains a small selection of many such auxiliary verbs.

• Note: {{nihongo3||得る|eru/uru}} is the only modern verb of shimo nidan type (and it is different from the shimo nidan type of classical Japanese), with conjugations: irrealis {{lang|ja|え}}, continuative {{lang|ja|え}}, terminal {{lang|ja|える}} or {{lang|ja|うる}}, attributive {{lang|ja|うる}}, hypothetical {{lang|ja|うれ}}, imperative {{lang|ja|えろ}} or {{lang|ja|えよ}}.

{{notelist}}

{{reflist}}

• {{cite journal |last1=Dixon |first1=R. M. W. |title=Where Have all the Adjectives Gone? |journal=Studies in Language |date=1 January 1977 |volume=1 |issue=1 |pages=19–80 |doi=10.1075/sl.1.1.04dix}}
• {{cite book |last=Kuno |first=Susumu |date=1973 |title=The structure of the Japanese language |place=Cambridge, MA |publisher=MIT Press |isbn=0-262-11049-0}}
• {{cite book |last=Shibatani |first=Masayoshi |date=1990b |title=The languages of Japan |place=Cambridge |publisher=Cambridge University Press}} {{ISBN|0-521-36070-6}} (hbk); {{ISBN|0-521-36918-5}} (pbk).
• {{cite book|last=Uehara |first=Satoshi|year= 1998|title= Syntactic categories in Japanese: a cognitive and typological introduction|publisher= Kurosio|series= Studies in Japanese linguistics|volume= 9|isbn=487424162X}}

• Bloch, Bernard. (1946). Studies in colloquial Japanese I: Inflection. Journal of the American Oriental Society, 66, 97–109.
• Bloch, Bernard. (1946). Studies in colloquial Japanese II: Syntax. Language, 22, 200–248.
• Chafe, William L. (1976). Giveness, contrastiveness, definiteness, subjects, topics, and point of view. In C. Li (Ed.), Subject and topic (pp. 25–56). New York: Academic Press. {{ISBN|0-12-447350-4}}.
• Jorden, Eleanor Harz, Noda, Mari. (1987). Japanese: The Spoken Language
• Katsuki-Pestemer, Noriko. (2009): A Grammar of Classical Japanese. München: LINCOM. {{ISBN|978-3-929075-68-7}}.
• Kiyose, Gisaburo N. (1995). Japanese Grammar: A New Approach. Kyoto: Kyoto University Press. {{ISBN|4-87698-016-0}}.
• Kuno, Susumu. (1976). Subject, theme, and the speaker's empathy: A re-examination of relativization phenomena. In Charles N. Li (Ed.), Subject and topic (pp. 417–444). New York: Academic Press. {{ISBN|0-12-447350-4}}.
• Makino, Seiichi & Tsutsui, Michio. (1986). A dictionary of basic Japanese grammar. Japan Times. {{ISBN|4-7890-0454-6}}
• Makino, Seiichi & Tsutsui, Michio. (1995). A dictionary of intermediate Japanese grammar. Japan Times. {{ISBN|4-7890-0775-8}}
• Martin, Samuel E. (1975). A reference grammar of Japanese. New Haven: Yale University Press. {{ISBN|0-300-01813-4}}.
• McClain, Yoko Matsuoka. (1981). Handbook of modern Japanese grammar: 口語日本文法便覧 [Kōgo Nihon bunpō benran]. Tokyo: Hokuseido Press. {{ISBN|4-590-00570-0}}; {{ISBN|0-89346-149-0}}.
• Mizutani, Osamu; & Mizutani, Nobuko. (1987). How to be polite in Japanese: 日本語の敬語 [Nihongo no keigo]. Tokyo: Japan Times. {{ISBN|4-7890-0338-8}}.
• {{cite book |last=Shibatani |first=Masayoshi |date=1990a |chapter=Japanese |editor=B. Comrie |title=The major languages of east and south-east Asia |place=London |publisher=Routledge |isbn=0-415-04739-0}}
• Shibamoto, Janet S. (1985). Japanese women's language. New York: Academic Press. {{ISBN|0-12-640030-X}}. Graduate Level
• Tsujimura, Natsuko. (1996). An introduction to Japanese linguistics. Cambridge, MA: Blackwell Publishers. {{ISBN|0-631-19855-5}} (hbk); {{ISBN|0-631-19856-3}} (pbk). Upper Level Textbooks
• Tsujimura, Natsuko. (Ed.) (1999). The handbook of Japanese linguistics. Malden, MA: Blackwell Publishers. {{ISBN|0-631-20504-7}}. Readings/Anthologies

{{Wikibooks|Japanese|Grammar/Transitivity|Transitivity}}

• [http://www.sljfaq.org/afaq/afaq.html FAQ] from the Usenet newsgroup sci.lang.japan
• [https://pomax.github.io/nrGrammar/ An introduction to Japanese - Syntax, Grammar & Language], online version by Michiel Kamermans
• [http://www.guidetojapanese.org/learn/grammar Tae Kim's Guide to Learning Japanese]  – Japanese online grammar guide
• Shoko Hamano, [http://www.gwu.edu/~eall/vjg/vjghomepage/vjghome.htm Visualizing Japanese Grammar] – animated Japanese grammar lessons from George Washington University

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{{Language grammars}}