Thai language#Old Thai

{{Further|Kra–Dai languages|Tai languages|Tai peoples}}

Standard Thai is classified as one of the Chiang Saen languages—others being Northern Thai, Southern Thai and numerous smaller languages, which together with the Northwestern Tai and Lao-Phutai languages, form the Southwestern branch of Tai languages. The Tai languages are a branch of the Kra–Dai language family, which encompasses a large number of indigenous languages spoken in an arc from Hainan and Guangxi south through Laos and Northern Vietnam to the Cambodian border.

Standard Thai is the principal language of education and government and spoken throughout Thailand. The standard is based on the dialect of the central Thai people, and it is written in the Thai script.

File:"tooth" in Kra-Dai languages.svg

{{clade

|label1=Kra-Dai

|1={{clade

| 1=Hlai languages

| 2=Kam-Sui languages

| 3=Kra languages

| 4=Be language

| label5=Tai languages

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| 1=Northern Tai languages

| 2=Central Tai languages

| label4=Southwestern Tai languages

| 4={{clade

| label1=Northwestern Tai languages

| 1={{clade

| 1=Khamti language

| 2=Tai Lue language

| 3=Shan language

| 4=others}}

| label2=Chiang Saen languages

| 2={{clade

| 1=Northern Thai language

| label2=Sukhothai language

| 2={{clade

| 1=Thai language

| 2=Southern Thai language}}}}

| label3=Lao-Phuthai languages

| 3={{clade

| 1=Tai Yo language

| 2=Phuthai language

| 3=Lao language (PDR Lao, Isan language)

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{{More citations needed section|date=May 2020}}

Thai has undergone various historical sound changes. Some of the most significant changes occurred during the evolution from Old Thai to modern Thai. The Thai writing system has an eight-century history and many of these changes, especially in consonants and tones, are evidenced in the modern orthography.

According to a Chinese source, during the Ming dynasty, Yingya Shenglan (1405–1433), Ma Huan reported on the language of the Xiānluó (暹羅) or Ayutthaya Kingdom,{{efn|Xiānluó was the Chinese name for Ayutthaya, a kingdom created by the merger of Lavo and Sukhothai or Suvarnabhumi.}} saying that it somewhat resembled the local patois as pronounced in Guangdong{{Citation|title=Ying-yai Sheng-lan: The Overall Survey of the Ocean's Shores (1433)|date=1970|publisher=Hakluyt Society at the University Press|isbn=0-521-01032-2}}{{rp|107}} Ayutthaya, the old capital of Thailand from 1351 - 1767 A.D., was from the beginning a bilingual society, speaking Thai and Khmer. Bilingualism must have been strengthened and maintained for some time by the great number of Khmer-speaking captives the Thais took from Angkor Thom after their victories in 1369, 1388 and 1431.Kasetsiri 1999: 25 Gradually toward the end of the period, a language shift took place. Khmer fell out of use. Both Thai and Khmer descendants whose great-grand parents or earlier ancestors were bilingual came to use only Thai. In the process of language shift, an abundance of Khmer elements were transferred into Thai and permeated all aspects of the language. Consequently, the Thai of the late Ayutthaya Period which later became Ratanakosin or Bangkok Thai, was a thorough mixture of Thai and Khmer. There were more Khmer words in use than Tai cognates. Khmer grammatical rules were used actively to coin new disyllabic and polysyllabic words and phrases. Khmer expressions, sayings, and proverbs were expressed in Thai through transference.

Thais borrowed both the Royal vocabulary and rules to enlarge the vocabulary from Khmer.Varasarin 1984: 91 The Thais later developed the royal vocabulary according to their immediate environment. Thai and Pali, the latter from Theravada Buddhism, were added to the vocabulary. An investigation of the Ayutthaya Rajasap reveals that three languages, Thai, Khmer and Khmero-Indic were at work closely both in formulaic expressions and in normal discourse. In fact, Khmero-Indic may be classified in the same category as Khmer because Indic had been adapted to the Khmer system first before the Thai borrowed.

Old Thai had a three-way tone distinction on "live syllables" (those not ending in a stop), with no possible distinction on "dead syllables" (those ending in a stop, i.e. either {{IPA|/p/, /t/, /k/}} or the glottal stop that automatically closes syllables otherwise ending in a short vowel).

There was a two-way voiced vs. voiceless distinction among all fricative and sonorant consonants, and up to a four-way distinction among stops and affricates. The maximal four-way occurred in labials ({{IPA|/p pʰ b ʔb/}}) and denti-alveolars ({{IPA|/t tʰ d ʔd/}}); the three-way distinction among velars ({{IPA|/k kʰ ɡ/}}) and palatals ({{IPA|/tɕ tɕʰ dʑ/}}), with the glottalized member of each set apparently missing.

The major change between old and modern Thai was due to voicing distinction losses and the concomitant tone split. This may have happened between about 1300 and 1600 CE, possibly occurring at different times in different parts of the Thai-speaking area. All voiced–voiceless pairs of consonants lost the voicing distinction:

• Plain voiced stops ({{IPA|/b d ɡ dʑ/}}) became voiceless aspirated stops ({{IPA|/pʰ tʰ kʰ tɕʰ/}}).The glottalized stops {{IPA|/ʔb ʔd/}} were unaffected, as they were treated in every respect like voiceless unaspirated stops due to the initial glottal stop. These stops are often described in the modern language as phonemically plain stops {{IPA|/b d/}}, but the glottalization is still commonly heard.
• Voiced fricatives became voiceless.
• Voiceless sonorants became voiced.

However, in the process of these mergers, the former distinction of voice was transferred into a new set of tonal distinctions. In essence, every tone in Old Thai split into two new tones, with a lower-pitched tone corresponding to a syllable that formerly began with a voiced consonant, and a higher-pitched tone corresponding to a syllable that formerly began with a voiceless consonant (including glottalized stops). An additional complication is that formerly voiceless unaspirated stops/affricates (original {{IPA|/p t k tɕ ʔb ʔd/}}) also caused original tone 1 to lower, but had no such effect on original tones 2 or 3.

The above consonant mergers and tone splits account for the complex relationship between spelling and sound in modern Thai. Modern "low"-class consonants were voiced in Old Thai, and the terminology "low" reflects the lower tone variants that resulted. Modern "mid"-class consonants were voiceless unaspirated stops or affricates in Old Thai—precisely the class that triggered lowering in original tone 1 but not tones 2 or 3. Modern "high"-class consonants were the remaining voiceless consonants in Old Thai (voiceless fricatives, voiceless sonorants, voiceless aspirated stops). The three most common tone "marks" (the lack of any tone mark, as well as the two marks termed mai ek and mai tho) represent the three tones of Old Thai, and the complex relationship between tone mark and actual tone is due to the various tonal changes since then. Since the tone split, the tones have changed in actual representation to the point that the former relationship between lower and higher tonal variants has been completely obscured. Furthermore, the six tones that resulted after the three tones of Old Thai were split have since merged into five in standard Thai, with the lower variant of former tone 2 merging with the higher variant of former tone 3, becoming the modern "falling" tone.Modern Lao, Isan and northern Thai dialects are often described as having six tones, but these are not necessarily due to preservation of the original six tones resulting from the tone split. For example, in standard Lao, both the high and low variants of Old Thai tone 2 merged; however, the mid-class variant of tone 1 became pronounced differently from either the high-class or low-class variants, and all three eventually became phonemic due to further changes, e.g. {{IPA|/kr/}} > {{IPA|/kʰ/}}. For similar reasons, Lao has developed more than two tonal distinctions in "dead" syllables.

{{further|Proto-Tai}}

Early Old Thai also apparently had velar fricatives {{IPA|/x ɣ/}} as distinct phonemes. These were represented by the now-obsolete letters ฃ kho khuat and ฅ kho khon, respectively. During the Old Thai period, these sounds merged into the corresponding stops {{IPA|/kʰ ɡ/}}, and as a result the use of these letters became unstable.

At some point in the history of Thai, an alveolo-palatal nasal phoneme {{IPA|/ɲ/}} also existed, inherited from Proto-Tai. A letter ญ yo ying also exists, which is used to represent an alveolo-palatal nasal in words borrowed from Sanskrit and Pali, and is currently pronounced {{IPA|/j/}} at the beginning of a syllable but {{IPA|/n/}} at the end of a syllable. Most native Thai words that are reconstructed as beginning with {{IPA|/ɲ/}} are also pronounced {{IPA|/j/}} in modern Thai, but generally spelled with ย yo yak, which consistently represents {{IPA|/j/}}. This suggests that {{IPA|/ɲ/}} > {{IPA|/j/}} in native words occurred in the pre-literary period. It is unclear whether Sanskrit and Pali words beginning with {{IPA|/ɲ/}} were borrowed directly with a {{IPA|/j/}}, or whether a {{IPA|/ɲ/}} was re-introduced, followed by a second change {{IPA|/ɲ/}} > {{IPA|/j/}}. The northeastern Thai dialect Isan and the Lao language still preserve the phoneme /ɲ/, which is represented in the Lao script by ຍ, such as in the word ຍຸງ ({{IPA|/ɲúŋ/}}, mosquito). This letter is distinct from the phoneme {{IPA|/j/}} and its Lao letter ຢ, such as in the word ຢາ ({{IPA|/jàː/}}, medicine). The distinction in writing has been lost in the informal writing of the Isan language with the Thai script and both sounds are represented by ย {{IPA|/j/}} (See: Comparison of Lao and Isan).

Proto-Tai also had a glottalized palatal sound, reconstructed as {{IPA|/ʔj/}} in Li Fang-Kuei (1977{{Full citation needed|date=November 2012}}). Corresponding Thai words are generally spelled หย, which implies an Old Thai pronunciation of {{IPA|/hj/}} (or {{IPA|/j̊/}}), but a few such words are spelled อย, which implies a pronunciation of {{IPA|/ʔj/}} and suggests that the glottalization may have persisted through to the early literary period.

The vowel system of modern Thai contains nine pure vowels and three centering diphthongs, each of which can occur short or long. According to Li (1977{{Full citation needed|date=November 2012}}), however, many Thai dialects have only one such short–long pair ({{IPA|/a aː/}}), and in general it is difficult or impossible to find minimal short–long pairs in Thai that involve vowels other than {{IPA|/a/}} and where both members have frequent correspondences throughout the Tai languages. More specifically, he notes the following facts about Thai:

• In open syllables, only long vowels occur. (This assumes that all apparent cases of short open syllables are better described as ending in a glottal stop. This makes sense from the lack of tonal distinctions in such syllables, and the glottal stop is also reconstructible across the Tai languages.)
• In closed syllables, the long high vowels {{IPA|/iː ɯː uː/}} are rare, and cases that do exist typically have diphthongs in other Tai languages.
• In closed syllables, both short and long mid {{IPA|/e eː o oː/}} and low {{IPA|/ɛ ɛː ɔ ɔː/}} do occur. However, generally, only words with short {{IPA|/e o/}} and long {{IPA|/ɛː ɔː/}} are reconstructible back to Proto-Tai.
• Both of the mid back unrounded vowels {{IPA|/ɤ ɤː/}} are rare, and words with such sounds generally cannot be reconstructed back to Proto-Tai.

Furthermore, the vowel that corresponds to short Thai {{IPA|/a/}} has a different and often higher quality in many of the Tai languages compared with the vowel corresponding to Thai {{IPA|/aː/}}.

This leads Li to posit the following:

1. Proto-Tai had a system of nine pure vowels with no length distinction, and possessing approximately the same qualities as in modern Thai: high {{IPA|/i ɯ u/}}, mid {{IPA|/e ɤ o/}}, low {{IPA|/ɛ a ɔ/}}.
2. All Proto-Tai vowels were lengthened in open syllables, and low vowels were also lengthened in closed syllables.
3. Modern Thai largely preserved the original lengths and qualities, but lowered {{IPA|/ɤ/}} to {{IPA|/a/}}, which became short {{IPA|/a/}} in closed syllables and created a phonemic length distinction {{IPA|/a aː/}}. Eventually, length in all other vowels became phonemic as well and a new {{IPA|/ɤ/}} (both short and long) was introduced, through a combination of borrowing and sound change. Li believes that the development of long {{IPA|/iː ɯː uː/}} from diphthongs, and the lowering of {{IPA|/ɤ/}} to {{IPA|/a/}} to create a length distinction {{IPA|/a aː/}}, had occurred by the time of Proto-Southwestern-Tai, but the other missing modern Thai vowels had not yet developed.

Not all researchers agree with Li. Pittayaporn (2009{{Full citation needed|date=November 2012}}), for example, reconstructs a similar system for Proto-Southwestern-Tai, but believes that there was also a mid back unrounded vowel {{IPA|/ə/}} (which he describes as {{IPA|/ɤ/}}), occurring only before final velar {{IPA|/k ŋ/}}. He also seems to believe that the Proto-Southwestern-Tai vowel length distinctions can be reconstructed back to similar distinctions in Proto-Tai.

{{IPA notice}}

Standard Thai distinguishes three voice-onset times among plosive and affricate consonants:

• voiced
• tenuis (unvoiced, unaspirated)
• aspirated

Where English makes a distinction between voiced {{IPA|/b/}} and unvoiced aspirated {{IPA|/pʰ/}}, Thai distinguishes a third sound – the unvoiced, unaspirated {{IPA|/p/}} that occurs in English only as an allophone of {{IPA|/pʰ/}}, for example after an {{IPA|/s/}} as in the sound of the p in "spin". There is similarly a laminal denti-alveolar{{Citation needed|date=April 2024}} {{IPA|/d/}}, {{IPA|/t/}}, {{IPA|/tʰ/}} triplet in Thai. In the velar series there is a {{IPA|/k/}}, {{IPA|/kʰ/}} pair and in the postalveolar series a {{IPA|/tɕ/}}, {{IPA|/tɕʰ/}} pair, without the corresponding voiced sounds {{IPA|/ɡ/}} and {{IPA|/dʑ/}}. (In loanwords from English, English {{IPA|/ɡ/}} and {{IPA|/d͡ʒ/}} are borrowed as the tenuis stops {{IPA|/k/}} and {{IPA|/tɕ/}}.)

In each cell below, the first line indicates International Phonetic Alphabet (IPA), the second indicates the Thai characters in initial position. Note that several letters appearing in the same box have identical pronunciation. In such cases, one of the letters may serve as the "default", being more common and/or preferred for borrowings from English and such; for example, น in the case of "n" and ส for "s". The letter ห, the default "h" letter, is also used to help write certain tones (described below).

Although the overall 44 Thai consonant letters provide 21 sounds in case of initials, the case for finals is different. For finals, only eight sounds, as well as no sound, called mātrā ({{Wikt-lang|th|มาตรา}}) are used. To demonstrate, at the end of a syllable, บ ({{IPA|/b/}}) and ด ({{IPA|/d/}}) are devoiced, becoming pronounced as {{IPA|/p/}} and {{IPA|/t/}} respectively. Additionally, all plosive sounds are unreleased. Hence, final {{IPA|/p/}}, {{IPA|/t/}}, and {{IPA|/k/}} sounds are pronounced as {{IPA|[p̚]}}, {{IPA|[t̚]}}, and {{IPA|[k̚]}} respectively.

Of the consonant letters, excluding the disused ฃ and ฅ, six (ฉ ผ ฝ ห อ ฮ) cannot be used as a final and the other 36 are grouped as following.

In Thai, each syllable in a word is articulated independently, so consonants from adjacent syllables (i.e. heterosyllabic) show no sign of articulation as a cluster. Thai has specific phonotactical patterns that describe its syllable structure, including tautosyllabic consonant clusters, and vowel sequences. In core Thai words (i.e. excluding loanwords), only clusters of two consonants occur, of which there are 11 combinations:

• {{IPA|/kr/}} (กร), {{IPA|/kl/}} (กล), {{IPA|/kw/}} (กว)
• {{IPA|/kʰr/}} (ขร, คร), {{IPA|/kʰl/}} (ขล, คล), {{IPA|/kʰw/}} (ขว, คว)
• {{IPA|/pr/}} (ปร), {{IPA|/pl/}} (ปล)
• {{IPA|/pʰr/}} (พร), {{IPA|/pʰl/}} (ผล, พล)
• {{IPA|/tr/}} (ตร)

The number of clusters increases in loanwords such as {{IPA|/tʰr/}} (ทร) in {{Wikt-lang|th|อินทรา}} ({{IPA|/ʔīn.tʰrāː/}}, from Sanskrit indrā) or {{IPA|/fr/}} (ฟร) in {{Wikt-lang|th|ฟรี}} ({{IPA|/frīː/}}, from English free); however, these usually only occur in initial position, with either {{IPA|/r/}}, {{IPA|/l/}}, or {{IPA|/w/}} as the second consonant sound and not more than two sounds at a time. In addition, ก may be Romanized as "g" and ป as "b" in those specific clusters to distinguish them from the corresponded aspirated stops.

The vowel nuclei of the Thai language are given in the following table. The top entry in every cell is the symbol from the International Phonetic Alphabet, the second entry gives the spelling in the Thai script, where a dash (–) indicates the position of the initial consonant after which the vowel is pronounced. A second dash indicates that a final consonant follows.

File:Thai vowel chart (monophthongs).svg

File:Thai vowel chart (diphthongs).png

Each vowel quality occurs in long-short pairs: these are distinct phonemes forming distinct words in Thai.{{Harvcoltxt|Tingsabadh|Abramson|1993|p=25}}

The long-short pairs are as follows:

There are also opening and closing diphthongs in Thai, which {{Harvcoltxt|Tingsabadh|Abramson|1993}} analyze as {{IPA|/Vj/}} and {{IPA|/Vw/}}. For purposes of determining tone, those marked with an asterisk are sometimes classified as long:

Additionally, there are three triphthongs. For purposes of determining tone, those marked with an asterisk are sometimes classified as long:

{{multiple image|total_width=250

|width1=340 |height1=400 |image1=Mid tone (Thai).svg

|width2=340 |height2=400 |image2=Low tone (Thai).svg

|width3=340 |height3=400 |image3=Falling tone (Thai).svg

|width4=340 |height4=400 |image4=High tone (Thai).svg

|width5=340 |height5=400 |image5=Rising tone (Thai).svg

|footer=The five phonemic tones of Standard Thai pronounced with the syllable '/naː/': {{paragraph break}} center

}}

There are five phonemic tones: mid, low, falling, high, and rising, sometimes referred to in older reference works as rectus, gravis, circumflexus, altus, and demissus, respectively.Frankfurter, Oscar. Elements of Siamese grammar with appendices. American Presbyterian mission press, 1900 [https://books.google.com/books?id=h6U6AAAAMAAJ] (Full text available on Google Books) The table shows an example of both the phonemic tones and their phonetic realization, in the IPA. Moren & Zsiga (2006){{Cite journal |last1=Morén |first1=Bruce |last2=Zsiga |first2=Elizabeth |date=2006 |title=The Lexical and Post-Lexical Phonology of Thai Tones* |url=http://link.springer.com/10.1007/s11049-004-5454-y |journal=Natural Language & Linguistic Theory |language=en |volume=24 |issue=1 |pages=113–178 |doi=10.1007/s11049-004-5454-y |s2cid=170764533 |issn=0167-806X}} and Zsiga & Nitisaroj (2007){{Cite journal |last1=Zsiga |first1=Elizabeth |last2=Nitisaroj |first2=Rattima |date=2007 |title=Tone Features, Tone Perception, and Peak Alignment in Thai |url=http://journals.sagepub.com/doi/10.1177/00238309070500030301 |journal=Language and Speech |language=en |volume=50 |issue=3 |pages=343–383 |doi=10.1177/00238309070500030301 |pmid=17974323 |s2cid=18595049 |issn=0023-8309}} provide phonetic and phonological analyses of Thai tone realization.

File:Thai tones.svg

Notes:

1. Five-level tone value: Mid [33], Low [21], Falling [41], High [45], Rising [214]. Traditionally, the high tone was recorded as either [44] or [45]. This remains true for the older generation, but the high tone is changing to [334] among youngsters.Teeranon, Phanintra. (2007). [http://www.skase.sk/Volumes/JTL10/pdf_doc/1.pdf "The change of Standard Thai high tone: An acoustic study and a perceptual experiment"]. SKASE Journal of Theoretical Linguistics, 4(3), 1–16.Thepboriruk, Kanjana. (2010). [https://docs.google.com/viewer?a=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxzZWFsc2pvdXJuYWx8Z3g6NDljZWJlMjUzMGE0NGYyMw "Bangkok Thai Tones Revisited"]. Journal of the Southeast Asian Linguistics Society, 3(1), 86–105.
2. For the diachronic changes of tone value, see Pittayaporn (2007).Pittayaporn, Pittayawat. (2007). [https://web.archive.org/web/20191204144531/https://pdfs.semanticscholar.org/4b67/bdd99e7a42c241f4fee6edc93f4f17e54ce8.pdf "Directionality of Tone Change"]. Proceedings of the 16th International Congress of Phonetic Sciences (ICPhS XVI).
3. The full complement of tones exists only in so-called "live syllables", those that end in a long vowel or a sonorant ({{IPA|/m/, /n/, /ŋ/, /j/, /w/}}).
4. For "dead syllables", those that end in a plosive ({{IPA|/p/, /t/, /k/}}) or in a short vowel, only three tonal distinctions are possible: low, high, and falling. Because syllables analyzed as ending in a short vowel may have a final glottal stop (especially in slower speech), all "dead syllables" are phonetically checked, and have the reduced tonal inventory characteristic of checked syllables.

In some English loanwords, closed syllables with a long vowel ending in an obstruent sound have a high tone, and closed syllables with a short vowel ending in an obstruent sound have a falling tone.

From the perspective of linguistic typology, Thai can be considered to be an analytic language. The word order is subject–verb–object,{{Cite book|last=Warotamasikkhadit|first=Udom|url=https://wals.info/refdb/record/Warotamasikkhadit-1972|title=Thai Syntax|date=1972|publisher=Mouton.|location=The Hague}} although the subject is often omitted. Additionally, Thai is an isolating language lacking any form of inflectional morphology whatsoever.{{Citation|last=Bisang|first=W.|title=Verb serialisation, grammaticalisation, and attractor positions in Chinese, Hmong, Vietnamese, Thai and Khmer|date=1991|url=https://wals.info/refdb/record/Bisang-1991|work=Partizipation: das sprachliche Erfassen von Sachverhalten|pages=509–562|place=Tübingen|publisher=Narr|access-date=2021-05-02}} Thai pronouns are selected according to the gender and relative status of speaker and audience.

There is no morphological distinction between adverbs and adjectives. Many words can be used in either function. They follow the word they modify, which may be a noun, verb, or another adjective or adverb.

{{fs interlinear|lang=th|glossing4=yes|indent=3

|คน อ้วน

|khon uan

|/{{IPA|kʰōn}} {{IPA|ʔûa̯n}}/

|'a fat person'}}

{{fs interlinear|lang=th|glossing4=yes|indent=3

|คน ที่ อ้วน เร็ว

|khon thi uan reo

|/{{IPA|kʰōn}} {{IPA|tʰîː}} {{IPA|ʔûa̯n}} {{IPA|rēw}}/

|'a person who becomes fat quickly'}}

Comparatives take the form "A X {{lang|th|กว่า}} B" ({{lang|th-Latn|kwa}}, {{IPA|/kwàː/}}), 'A is more X than B'. The superlative is expressed as "A X {{lang|th|ที่สุด}}" ({{lang|th-Latn|thi sut}}, {{IPA|/tʰîː sùt/}}), 'A is most X'.

{{fs interlinear|lang=th|glossing4=yes|indent=3

|เขา อ้วน กว่า ฉัน

|khao uan kwa chan

|/{{IPA|kʰǎw}} {{IPA|ʔûa̯n}} {{IPA|kwàː}} {{IPA|tɕʰǎn}}/

|'S/he is fatter than me.'}}

{{fs interlinear|lang=th|glossing4=yes|indent=3

|เขา อ้วน ที่สุด

|khao uan {thi sut}

|/{{IPA|kʰǎw}} {{IPA|ʔûa̯n}} {{IPA|tʰîː sùt}}/

|'S/he is the fattest (of all).'}}

Adjectives in Thai can be used as complete predicates. Because of this, many words used to indicate tense in verbs (see Verbs:Tense below) may be used to describe adjectives.

{{fs interlinear|lang=th|glossing4=yes|indent=3

|ฉัน หิว

|chan hio

|/{{IPA|tɕʰǎn}} {{IPA|hǐw}}/

|'I am hungry.'}}

{{fs interlinear|lang=th|glossing4=yes|indent=3

|ฉัน จะ หิว

|chan cha hio

|/{{IPA|tɕʰǎn}} {{IPA|tɕàʔ}} {{IPA|hǐw}}/

|'I will be hungry.'}}

{{fs interlinear|lang=th|glossing4=yes|indent=3

|ฉัน กำลัง หิว

|chan kamlang hio

|/{{IPA|tɕʰǎn}} {{IPA|kām.lāŋ}} {{IPA|hǐw}}/

|'I am hungry right now.'}}

{{fs interlinear|lang=th|glossing4=yes|indent=3

|ฉัน หิว แล้ว

|chan hio laeo

|/{{IPA|tɕʰǎn}} {{IPA|hǐw}} {{IPA|lɛ́ːw}}/

|'I am already hungry.'}}

:* Remark {{lang|th|ฉันหิวแล้ว}} mostly means 'I am hungry right now' because normally, {{lang|th|แล้ว}} ({{IPA|/lɛ́ːw/}}) marks the change of a state, but {{lang|th|แล้ว}} has many other uses as well. For example, in the sentence, {{lang|th|แล้วเธอจะไปไหน}} ({{IPA|/lɛ́ːw tʰɤ̄ː tɕàʔ pāj nǎj/}}): 'So where are you going?', {{lang|th|แล้ว}} ({{IPA|/lɛ́ːw/}}) is used as a discourse particle.

Verbs do not inflect. They do not change with person, tense, voice, mood, or number; nor are there any participles. The language being analytic and case-less, the relationship between subject, direct and indirect object is conveyed through word order and auxiliary verbs. Transitive verbs follow the pattern subject-verb-object.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ฉัน ตี เขา

|chan ti khao

|/{{IPA|tɕʰǎn}} {{IPA|tīː}} {{IPA|kʰǎw}}/

|1SG hit 3SG

|'I hit him.'}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ตี ฉัน

|khao ti chan

|/{{IPA|kʰǎw}} {{IPA|tīː}} {{IPA|tɕʰǎn}}/

|3SG hit 1SG

|'S/He hit me.'}}

In order to convey tense, aspect and mood (TAM), the Thai verbal system employs auxiliaries and verb serialization.{{Citation |last1=Jenny |first1=Mathias |title=The aspect system of Thai |date=2001 |url=https://www.zora.uzh.ch/id/eprint/110203/ |work=Aktionsart and Aspectotemporality in non-European languages |pages=97–140 |place=Zürich |publisher=Seminar für Allgemeine Sprachwissenschaft, Universität Zürich |isbn=978-3-9521010-8-7 |access-date=2021-05-02 |last2=Ebert |first2=Karen H. |last3=Zúñiga |first3=Fernando }} TAM markers are however not obligatory and often left out in colloquial use. In such cases, the precise meaning is determined through context. This results in sentences lacking both TAM markers and overt context being ambiguous and subject to various interpretations.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ฉัน กิน ที่ นั่น

|chan kin thi nan

|/{{IPA|tɕʰǎn}} {{IPA|kīn}} {{IPA|tʰîː}} {{IPA|nân}}/

|'I eat there.'}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ฉัน กิน ที่ นั่น เมื่อวาน

|chan kin thi nan mueawan

|/{{IPA|tɕʰǎn}} {{IPA|kīn}} {{IPA|tʰîː}} {{IPA|nân}} {{IPA|mɯ̂a̯.wāːn}}/

|'I ate there yesterday.'}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ฉัน จะ กิน ที่ นั่น พรุ่งนี้

|chan cha kin thi nan phrungni

|/{{IPA|tɕʰǎn}} {{IPA|tɕàʔ}} {{IPA|kīn}} {{IPA|thîː}} {{IPA|nân}} {{IPA|pʰrûŋ.níː}}/

|'I'll eat there tomorrow.'}}

The sentence {{lang|th-Latn|chan kin thi nan}} can thus be interpreted as 'I am eating there', 'I eat there habitually', 'I will eat there' or 'I ate there'. Aspect markers in Thai have been divided into four distinct groups based on their usage. These markers could appear either before or after the verb. The following list describes some of the most commonly used aspect markers. A number of these aspect markers are also full verbs on their own and carry a distinct meaning. For example {{lang|th-Latn|yu}} ({{lang|th|อยู่}}) as a full verb means 'to stay, to live or to remain at'. However, as an auxiliary it can be described as a temporary aspect or continuative marker.

• Imperfective
• {{lang|th|อยู่}} {{lang|th-Latn|yu}} {{IPA|/jùː/}}
• {{lang|th|ไป}} {{lang|th-Latn|pai}} {{IPA|/pāj/}}
• {{lang|th|ยัง}} {{lang|th-Latn|yang}} {{IPA|/jāŋ/}}
• {{lang|th|กำลัง}} {{lang|th-Latn|kamlang}} {{IPA|/kām.lāŋ/}}
• {{lang|th|เคย}} {{lang|th-Latn|khoey}} {{IPA|/kʰɤ̄ːj/}}
• Perfective
• {{lang|th|ได้}} {{lang|th-Latn|dai}} {{IPA|/dâːj/}}
• Perfect
• {{lang|th|แล้ว}} {{lang|th-Latn|laeo}} {{IPA|/lɛ́ːw/}}
• {{lang|th|มา}} {{lang|th-Latn|ma}} {{IPA|/māː/}}
• Prospective/Future
• {{lang|th|จะ}} {{lang|th-Latn|cha}} {{IPA|/tɕàʔ/}}

The imperfective aspect marker {{lang|th|กำลัง}} ({{lang|th-Latn|kamlang}}, {{IPA|/kām lāŋ/}}, currently) is used before the verb to denote an ongoing action (similar to the -ing suffix in English). {{lang|th-Latn|Kamlang}} is commonly interpreted as a progressive aspect marker.{{Cite book |last=Boonyapatipark |first=Tasanalai |url=https://books.google.com/books?id=rPRyuAAACAAJ |title=A study of aspect in Thai |date=1983 |publisher=University of London |language=en }}{{Cite journal |last1=Koenig |first1=Jean-Pierre |last2=Muansuwan |first2=Nuttanart |date=2005 |title=The Syntax of Aspect in Thai |url=https://www.jstor.org/stable/4048104 |journal=Natural Language & Linguistic Theory |volume=23 |issue=2 |pages=335–380 |doi=10.1007/s11049-004-0488-8 |jstor=4048104 |s2cid=170429648 |issn=0167-806X }} Similarly, {{lang|th|อยู่}} ({{lang|th-Latn|yu}}, {{IPA|/jùː/}}) is a post-verbal aspect marker which corresponds to the continuative or temporary aspect.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา กำลัง วิ่ง

|khao kamlang wing

|/{{IPA|kʰǎw}} {{IPA|kām.lāŋ}} {{IPA|wîŋ}}/

|}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา วิ่ง อยู่

|khao wing yu

|/{{IPA|kʰǎw}} {{IPA|wîŋ}} {{IPA|jùː}}/

|}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา กำลัง วิ่ง อยู่

|khao kamlang wing yu

|/{{IPA|kʰǎw}} {{IPA|kām.lāŋ}} {{IPA|wîŋ}} {{IPA|jùː}}/

|'He is running.'}}

Comparably {{lang|th|ยัง}} ({{lang|th-Latn|yang}}, {{IPA|/jāŋ/}}, still) which is used in an incompleted action, and usually cognates in phrase with {{lang|th-Latn|yu}} ({{lang|th|อยู่}}) or any second marker in common use.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ยัง เขียน อยู่

|khao yang khian yu

|/{{IPA|kʰǎw}} {{IPA|jāŋ}} {{IPA|kʰǐa̯n}} {{IPA|jùː}}/

|He is still writing.}}

The marker {{lang|th|ได้}} ({{lang|th-Latn|dai}}, {{IPA|/dâːj/}}) is usually analyzed as a past tense marker when it occurs before the verb. As a full verb, {{lang|th-Latn|dai}} means 'to get or receive'. However, when used after a verb, {{lang|th-Latn|dai}} takes on a meaning of potentiality or successful outcome of the main verb.

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เขา ได้ ไป เที่ยว เมือง ลาว

|khao dai pai thiao mueang lao

|/{{IPA|kʰǎw}} {{IPA|dâːj}} {{IPA|pāj}} {{IPA|tʰîa̯w}} {{IPA|mɯ̄aŋ}} {{IPA|lāːw}}/

|He visited Laos. (Past/Perfective)}}

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เขา ตี ได้

|khao ti dai

|/{{IPA|kʰǎw}} {{IPA|tīː}} {{IPA|dâːj}}/

|3SG hit POT

|'He is/was allowed to hit' or 'He is/was able to hit.' (Potentiality)}}

{{lang|th|แล้ว}} ({{lang|th-Latn|laeo}}, {{IPA|/lɛ́ːw/}}; 'already') is treated as a marker indicating the perfect aspect. That is to say, {{lang|th-Latn|laeo}} marks the event as being completed at the time of reference. {{lang|th-Latn|Laeo}} has two other meanings in addition to its use as a TAM marker. {{lang|th-Latn|Laeo}} can either be a conjunction for sequential actions or an archaic word for 'to finish'.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ได้ กิน

|khao dai kin

|/{{IPA|kʰǎw}} {{IPA|dâːj}} {{IPA|kīn}}/

|3SG PST eat

|He ate.}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา กิน แล้ว

|khao kin laeo

|/{{IPA|kʰǎw}} {{IPA|kīn}} {{IPA|lɛ́ːw}}/

|3SG eat PRF

|He has eaten.}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ได้ กิน แล้ว

|khao dai kin laeo

|/{{IPA|kʰǎw}} {{IPA|dâːj}} {{IPA|kīn}} {{IPA|lɛ́ːw}}/

|3SG PST eat PRF

|He's already eaten.}}

Future can be indicated by {{lang|th|จะ}} ({{lang|th-Latn|cha}}, {{IPA|/tɕàʔ/}}; 'will') before the verb or by a time expression indicating the future. For example:

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เขา จะ วิ่ง

|khao cha wing

|/{{IPA|kʰǎw}} {{IPA|tɕàʔ}} {{IPA|wîŋ}}/

|3SG FUT run

|'He will run' or 'He is going to run.'}}

Dative marker {{lang|th|ให้}} ({{lang|th-Latn|hai}}, {{IPA|/hâj/}}; 'give') often used in a sentence as prepositional or double objects.{{Cite web |title=The Acquisition Of Dative Constructions By Thai |url=http://ethesisarchive.library.tu.ac.th/thesis/2017/TU_2017_5521320084_8564_9178.pdf}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา อ่าน หนังสือ ให้

|khao an {nangsue} hai

|/{{IPA|kʰǎw}} {{IPA|ʔàːn}} {{IPA|nǎŋ.sɯ̌ː}} {{IPA|hâj}}/

|3SG read book DAT

|'He reads book for (us).'}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ให้ อ่าน หนังสือ

|khao hai an {nangsue}

|/{{IPA|kʰǎw}} {{IPA|hâj}} {{IPA|ʔàːn}} {{IPA|nǎŋ.sɯ̌ː}}/

|3SG DAT read book

|'He obligates (us) to read book.'}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|เขา ให้ หนังสือ นักเรียน

|khao hai {nangsue} {nak rian}

|/{{IPA|kʰǎw}} {{IPA|hâj}} {{IPA|nǎŋ.sɯ̌ː}} {{IPA|nák ria̯n}}/

|3SG DAT book student

|'He gives book to student.'}}

The passive voice is indicated by the insertion of {{lang|th|ถูก}} ({{lang|th-Latn|thuk}}, {{IPA|/tʰùːk/}}) before the verb. For example:

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เขา ถูก ตี

|khao thuk ti

|/{{IPA|kʰǎw}} {{IPA|tʰùːk}} {{IPA|tīː}}/

|3SG PASS hit

|'He got hit.'}}

::This describes an action that is out of the receiver's control and, thus, conveys suffering.

Negation is indicated by placing {{lang|th|ไม่}} ({{lang|th-Latn|mai}}, {{IPA|/mâj/}}; not) before the verb.

• {{lang|th|เขาไม่ตี}}, ({{lang|th-Latn|khao mai ti}}) 'He is not hitting' or 'He doesn't hit'.

Thai exhibits serial verb constructions, where verbs are strung together. Some word combinations are common and may be considered set phrases.

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เขา ไป กิน ข้าว

|khao pai kin khao

|/{{IPA|kʰǎw}} {{IPA|pāj}} {{IPA|kīn}} {{IPA|kʰâːw}}/

|he go eat rice

|'He went out to eat'}}

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|ฉัน ฟัง ไม่ เข้าใจ

|chan fang mai {khao chai}

|/{{IPA|tɕʰǎn}} {{IPA|fāŋ}} {{IPA|mâj}} {{IPA|kʰâw tɕāj}}/

|I listen not understand

|'I don't understand what was said'}}

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|เข้า มา

|khao ma

|/{{IPA|kʰâw}} {{IPA|māː}}/

|enter come

|'Come in'}}

{{fs interlinear|lang=th|glossing4=yes|number=ex:

|ออก ไป!

|ok pai

|/{{IPA|ʔɔ̀ːk}} {{IPA|pāj}}/

|exit go

|'Leave!' or 'Get out!'}}

Nouns are uninflected and have no gender; there are no articles. Thai nouns are bare nouns and can be interpreted as singular, plural, definite or indefinite.{{Cite thesis |last=Jenks |first=Peter |date=2011 |title=The Hidden Structure of Thai Noun Phrases |type=PhD dissertation |publisher=Harvard University |url=http://www.linguistics.berkeley.edu/~jenks/Research_files/Jenks_2011.pdf |archive-url=https://web.archive.org/web/20150503175806/http://linguistics.berkeley.edu/~jenks/Research_files/Jenks_2011.pdf |archive-date=2015-05-03 |url-status=live |isbn=978-1-267-10767-1 |s2cid=118127511 |id={{ProQuest|915016895}} }} Some specific nouns are reduplicated to form collectives: {{lang|th|เด็ก}} ({{lang|th-Latn|dek}}, 'child') is often repeated as {{lang|th|เด็ก ๆ}} ({{lang|th-Latn|dek dek}}) to refer to a group of children. The word {{lang|th|พวก}} ({{lang|th-Latn|phuak}}, {{IPA|/pʰûa̯k/}}) may be used as a prefix of a noun or pronoun as a collective to pluralize or emphasise the following word. ({{lang|th|พวกผม}}, {{lang|th-Latn|phuak phom}}, {{IPA|/pʰûa̯k pʰǒm/}}, 'we', masculine; {{lang|th|พวกเรา}} {{lang|th-Latn|phuak rao}}, {{IPA|/pʰûa̯k rāw/}}, emphasised 'we'; {{lang|th|พวกหมา}} {{lang|th-Latn|phuak ma}}, '(the) dogs'). Plurals are expressed by adding classifiers, used as measure words ({{lang|th|ลักษณนาม}}), in the form of noun-number-classifier:

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ครู ห้า คน

|khru ha khon

|/{{IPA|kʰrūː}} {{IPA|hâː}} {{IPA|kʰōn}}/

|teacher five person

|"five teachers"}}

While in English, such classifiers are usually absent ("four chairs") or optional ("two bottles of beer" or "two beers"), a classifier is almost always used in Thai (hence "chair four item" and "beer two bottle").

Possession in Thai is indicated by adding the word {{lang|th|ของ}} ({{lang|th-Latn|khong}}) in front of the noun or pronoun, but it may often be omitted. For example:

{{Col-begin}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ลูก ของ แม่

|luk khong mae

|/{{IPA|lûːk}} {{IPA|kʰɔ̌ːŋ}} {{IPA|mɛ̂ː}}/

|child {belonging to} mother

|"mother's child"}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|นา อา

|na a

|/{{IPA|nāː}} {{IPA|ʔāː}}/

|field uncle

|"uncle's field"{{Cite web|url=http://www.thailanguage.org/thai/grammar.asp|title=Thailanguage.org|access-date=18 September 2010|archive-date=11 November 2005|archive-url= https://web.archive.org/web/20051111090104/http://www.thailanguage.org/thai/grammar.asp|url-status=usurped}}}}

{{Col-end}}

Nominal phrases in Thai often use a special class of words classifiers. As previously mentioned, these classifiers are obligatory for noun phrases containing numerals e.g.

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ผู้หญิง สอง คน

|phuying song khon

|/{{IPA|pʰûː.jǐŋ}} {{IPA|sɔ̌ːŋ}} {{IPA|kʰōn}}/

|woman two CL

|two women}}

Unlike any numeral, {{lang|th|หนึ่ง}} ('one') can mark on both positions of classifier, but in different functions. The post-head one potentially marks a referent as indefinite article.

{{Col-begin}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|แก้ว หนึ่ง ใบ

|kaew neung bai

|/{{IPA|kɛ̂ːw}} {{IPA|nɯ̀ŋ}} {{IPA|bāj}}/

|glass one CL

|"one glass" (quantificational)}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|แก้ว ใบ หนึ่ง

|kaew bai neung

|/{{IPA|kɛ̂ːw}} {{IPA|bāj}} {{IPA|nɯ̀ŋ}}/

|glass CL one

|"a glass" (referential)}}

{{Col-end}}

In the previous example {{lang|th-Latn|khon}} ({{lang|th|คน}}) acts as the classifier in the nominal phrase. This follows the form of noun-cardinal-classifier mentioned above. Classifiers are also required to form quantified noun phrases in Thai with some quantifiers such as {{lang|th|ทุก}} ('all'), {{lang|th|บาง}} ('some'). The examples below are demonstrated using the classifier {{lang|th-Latn|khon}}, which is used for people.

{{Col-begin}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|{นักเรียน} ทุก คน

|{nak rian} thuk khon

|/{{IPA|nák rīa̯n}} {{IPA|tʰúk}} {{IPA|kʰōn}}/

|student every CL

|"every student"}}

{{Col-2}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|ครู บาง คน

|khru bang khon

|/{{IPA|kʰrūː}} {{IPA|bāːŋ}} {{IPA|kʰōn}}/

|teacher some CL

|"some teacher"}}

{{Col-end}}

However, classifiers are not utilized for negative quantification. Negative quantification is expressed by the pattern {{lang|th|ไม่มี}} ({{lang|th-Latn|mai mi}}, {{IPA|/mâj mīː/}}) + NOUN.

Thai has three of its distinctions. Proximal {{lang|th|นี่}} ({{lang|th-Latn|ni}}, {{IPA|/nîː/}}; 'this/these'), medial {{lang|th|นั่น}} ({{lang|th-Latn|nan}}, {{IPA|/nân/}}; 'that/those'), and distal {{lang|th|โน่น}} ({{lang|th-Latn|non}}, {{IPA|/nôːn/}}; 'that/those over there') which is rarely used.

It also has different usage of distinguishing the demonstratives by changing tones. In which the pronoun itself used for {{lang|th|นี่}} ({{lang|th-Latn|ni}}, {{IPA|/nîː/}}); while {{lang|th|นี้}} ({{lang|th-Latn|ni}}, {{IPA|/níː}}) refers to be modifier placed after the noun, prepositions, classifiers, etc. For example:

{{fs interlinear|lang=th|indent=3|glossing4=yes

|นี่ คือ โต๊ะ ใหม่

|ni kheu to mai

|/{{IPA|nîː}} {{IPA|kʰɯ̄ː}} {{IPA|tóʔ}} {{IPA|màj}}/

|this-PRO be table new

|"this is a new table"}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|วาง ถ้วย บน นั้น

|wang thuai bon nan

|/{{IPA|wāːŋ}} {{IPA|tʰûa̯j}} {{IPA|bōn}} {{IPA|nán}}/

|{put down} bowl on that-PREP

|"put a bowl on there"}}

Following the word {{lang|th|ไหน}} ({{lang|th-Latn|nai}}, {{IPA|/nǎj/}}) which plays role as interrogative determiner or pronoun.

{{Col-begin}}

{{Col-3}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|แมว ตัว ไหน

|maew tua nai

|/{{IPA|mɛ̄ːw}} {{IPA|tūa̯}} {{IPA|nǎj}}/

|cat CL INT

|"which cat?"}}

{{Col-3}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|จอด ที่ ไหน

|joat thi nai

|/{{IPA|t͡ɕɔ̀ːt}} {{IPA|tʰîː}} {{IPA|nǎj}}/

|park PREP INT

|"where to park?"}}

{{Col-3}}

{{fs interlinear|lang=th|indent=3|glossing4=yes

|พัก ตอน ไหน

|phak toan nai

|/{{IPA|pʰák}} {{IPA|tɔ̄ːn}} {{IPA|nǎj}}/

|rest since INT

|"when to rest?"}}

{{Col-end}}

The syntax for demonstrative phrases, however, differ from that of cardinals and follow the pattern noun-classifier-demonstrative. For example, the noun phrase "this dog" would be expressed in Thai as {{lang|th|หมาตัวนี้}} (literally 'dog (classifier) this').{{Cite book|last=Smyth|first=David |title=Thai|date=2014|publisher=Taylor and Francis|isbn=978-1-317-97457-4|edition=2nd |location=Hoboken|oclc=879025983}}

Subject pronouns are often omitted, with nicknames used where English would use a pronoun. See Thai name#Nicknames for more details. Pronouns, when used, are ranked in honorific registers, and may also make a T–V distinction in relation to kinship and social status. Specialised pronouns are used for royalty, and for Buddhist monks. The following are appropriate for conversational use:

The reflexive pronoun is {{lang|th|ตัวเอง}} ({{lang|th-Latn|tua eng}}), which can mean any of: myself, yourself, ourselves, himself, herself, themselves. This can be mixed with another pronoun to create an intensive pronoun, such as {{lang|th|ตัวผมเอง}} ({{lang|th-Latn|tua phom eng}}, lit: I myself) or {{lang|th|ตัวคุณเอง}} ({{lang|th-Latn|tua khun eng}}, lit: you yourself). Thai also does not have a separate possessive pronoun. Instead, possession is indicated by the particle {{lang|th|ของ}} ({{lang|th-Latn|khong}}). For example, "my mother" is {{lang|th|แม่ของผม}} ({{lang|th-Latn|mae khong phom}}, lit: mother of I). This particle is often implicit, so the phrase is shortened to {{lang|th|แม่ผม}} ({{lang|th-Latn|mae phom}}). Plural pronouns can be easily constructed by adding the word {{lang|th|พวก}} ({{lang|th-Latn|phuak}}) in front of a singular pronoun as in {{lang|th|พวกเขา}} ({{lang|th-Latn|phuak khao}}) meaning 'they' or {{lang|th|พวกเธอ}} ({{lang|th-Latn|phuak thoe}}) meaning the plural sense of 'you'. The only exception to this is {{lang|th|เรา}} ({{lang|th-Latn|rao}}), which can be used as singular (informal) or plural, but can also be used in the form of {{lang|th|พวกเรา}} ({{lang|th-Latn|phuak rao}}), which is only plural.

Thai has many more pronouns than those listed above. Their usage is full of nuances. For example:

• "{{lang|th|ผม เรา ฉัน ดิฉัน หนู กู ข้า กระผม ข้าพเจ้า กระหม่อม อาตมา กัน ข้าน้อย ข้าพระพุทธเจ้า อั๊ว เขา}}" all translate to "I", but each expresses a different gender, age, politeness, status, or relationship between speaker and listener.
• {{lang|th|เรา}} ({{lang|th-Latn|rao}}) can be first person (I), second person (you), or both (we), depending on the context.
• Children or younger female could use or being referred by word {{lang|th|หนู}} ({{lang|th-Latn|nu}}) when talking with older person. The word {{lang|th|หนู}} could be both feminine first person (I) and feminine second person (you) and also neuter first and neuter second person for children.
• {{lang|th|หนู}} commonly means rat or mouse, though it also refers to small creatures in general.
• The second person pronoun {{lang|th|เธอ}} ({{lang|th-Latn|thoe}}) (lit: you) is semi-feminine. It is used only when the speaker or the listener (or both) are female. Males usually do not address each other by this pronoun.
• Both {{lang|th|คุณ}} ({{lang|th-latn|khun}}) and {{lang|th|เธอ}} ({{lang|th-Latn|thoe}}) are polite neuter second person pronouns. However, {{lang|th|คุณเธอ}} ({{lang|th-Latn|khun thoe}}) is a feminine derogative third person.
• Instead of a second person pronoun such as {{lang|th|คุณ}} ('you'), it is much more common for unrelated strangers to call each other {{lang|th|พี่ น้อง ลุง ป้า น้า อา ตา}} or {{lang|th|ยาย}} (brother, sister, aunt, uncle, granny).
• To express deference, the second person pronoun is sometimes replaced by a profession, similar to how, in English, presiding judges are always addressed as "your honor" rather than "you". In Thai, students always address their teachers by {{lang|th|ครู}}, {{lang|th|คุณครู}} or {{lang|th|อาจารย์}} (each meaning 'teacher') rather than {{lang|th|คุณ}} ('you'). Teachers, monks, and doctors are almost always addressed this way.

The particles are often untranslatable words added to the end of a sentence to indicate respect, a request, encouragement or other moods (similar to the use of intonation in English), as well as varying the level of formality. They are not used in elegant (written) Thai. The most common particles indicating respect are {{lang|th|ครับ}} ({{lang|th-Latn|khrap}}, {{IPA|/kʰráp/}}, with a high tone) when the speaker is a man, and {{lang|th|ค่ะ}} ({{lang|th-Latn|kha}}, {{IPA|/kʰâʔ/}}, with a falling tone) when the speaker is a woman. Used in a question or a request, the particle {{lang|th|ค่ะ}} (falling tone) is changed to a {{lang|th|คะ}} (high tone).

Other common particles are:

Central Thai is composed of several distinct registers, forms for different social contexts:

• Street or Common Thai ({{Wikt-lang|th|ภาษาพูด}}, {{lang|th-Latn|phasa phut}}, spoken Thai): informal, without polite terms of address, as used between close relatives and friends.
• Elegant or Formal Thai ({{Wikt-lang|th|ภาษาเขียน}}, {{lang|th-Latn|phasa khian}}, written Thai): official and written version, includes respectful terms of address; used in simplified form in newspapers.
• Rhetorical Thai: used for public speaking.
• Religious Thai: (heavily influenced by Sanskrit and Pāli) used when discussing Buddhism or addressing monks.
• Royal Thai ({{lang|th|ราชาศัพท์}}, {{lang|th-Latn|racha sap}}): influenced by Khmer, this is used when addressing members of the royal family or describing their activities. (See {{section link|Monarchy of Thailand|Rachasap}}.)

Most Thais can speak and understand all of these contexts. Street and Elegant Thai are the basis of all conversations.{{Cite web|url=http://www.studycountry.com/guide/TH-language.htm|title=The Languages spoken in Thailand|website=Studycountry|language=en-US|access-date=2017-12-26}}{{Citation needed|date=March 2009}} Rhetorical, religious, and royal Thai are taught in schools as part of the national curriculum.

As noted above, Thai has several registers, each having certain usages, such as colloquial, formal, literary, and poetic. Thus, the word 'eat' can be {{lang|th|กิน}} ({{lang|th-Latn|kin}}; common), {{lang|th|แดก}} ({{lang|th-Latn|daek}}; vulgar), {{lang|th|ยัด}} ({{lang|th-Latn|yat}}; vulgar), {{lang|th|บริโภค}} ({{lang|th-Latn|boriphok}}; formal), {{lang|th|รับประทาน}} ({{lang|th-Latn|rapprathan}}; formal), {{lang|th|ฉัน}} ({{lang|th-Latn|chan}}; religious), or {{lang|th|เสวย}} ({{lang|th-Latn|sawoei}}; royal), as illustrated below:

Thailand also uses the distinctive Thai six-hour clock in addition to the 24-hour clock.

{{Main|List of loanwords in Thai|List of Thai language idioms}}

Other than compound words and words of foreign origin, most words are monosyllabic.

Chinese-language influence was strong until the 13th century when the use of Chinese characters was abandoned, and replaced by Sanskrit and Pali scripts. However, the vocabulary of Thai retains many words borrowed from Middle Chinese.{{cite book |first1=Martin |last1=Haspelmath |first2=Uri |last2=Tadmor |title=Loanwords in the World's Languages: A Comparative Handbook |date=2009 |page=611 |quote=Thai is of special interest to lexical borrowing for various reasons. The copious borrowing of basic vocabulary from Middle Chinese and later from Khmer indicates that, given the right sociolinguistic context, such vocabulary is not at all immune }}{{cite book |first=Harald |last=Haarmann |title=Language in Ethnicity: A View of Basic Ecological Relations |date=1986 |page=165 |quote=In Thailand, for instance, where the Chinese influence was strong until the Middle Ages, Chinese characters were abandoned in written Thai in the course of the thirteenth century. }}{{cite book |first=Paul A. |last=Leppert |title=Doing Business With Thailand |date=1992 |page=13 |quote=At an early time the Thais used Chinese characters. But, under the influence of Indian traders and monks, they soon dropped Chinese characters in favor of Sanskrit and Pali scripts. }}

Khmer was used as a prestige language in the early days of the Thai kingdoms which are believed to have been bilingual societies proficient in Thai and Khmer. There are over 2,500 Thai words derived from Khmer, surpassing the number of Tai cognates. These Khmer words span across all semantic fields. Thai scholar Uraisi Varasarin classified them into over 200 sub-categories. As a result, it is impossible for Thais, past and present, to engage in a conversation without incorporating Khmer loanwords in any given topic. The influence is particularly preponderant in regard to royal court terminology.{{cite journal |last1= Khanittanan |first1= Wilaiwan |date= 2004 |title=Khmero-Thai: The Great Change in the History of the Thai Language of the Chao Phraya Basin|journal= Annual Meeting of the Southeast Asian Linguistics Society |volume= 11 |url=http://sealang.net/sala/archives/pdf4/wilaiwan2004khmero.pdf}}

Later, most vocabulary was borrowed from Sanskrit and Pāli; Buddhist terminology is particularly indebted to these. Indic words have a more formal register, and may be compared to Latin and French borrowings in English. Since the beginning of the 20th century, however, the English language has had the greatest influence, especially for scientific, technical, international, and other modern terms.

From Middle Chinese or Teochew Chinese.

From Old Khmer

The Portuguese were the first Western nation to arrive in what is modern-day Thailand in the 16th century during the Ayutthaya period. Their influence in trade, especially weaponry, allowed them to establish a community just outside the capital and practise their faith, as well as exposing and converting the locals to Christianity. Thus, Portuguese words involving trade and religion were introduced and used by the locals.

{{Main|Thai script|Thai braille}}

File:Kingdom of Thailand.svg

Thai is written in the Thai script, an abugida written from left to right. The language and its script are closely related to the Lao language and script. Most literate Lao are able to read and understand Thai, as more than half of the Thai vocabulary, grammar, intonation, vowels and so forth are common with the Lao language.

The Thais adopted and modified the Khmer script to create their own writing system. While in Thai the pronunciation can largely be inferred from the script, the orthography is complex, with silent letters to preserve original spellings and many letters representing the same sound. While the oldest known inscription in the Khmer language dates from 611 CE, inscriptions in Thai writing began to appear around 1292 CE. Notable features include:

1. It is an abugida script, in which the implicit vowel is a short {{IPA|/a/}} in a syllable without final consonant and a short {{IPA|/o/}} in a syllable with final consonant.
2. Tone markers, if present, are placed above the final onset consonant of the syllable.
3. Vowels sounding after an initial consonant can be located before, after, above or below the consonant, or in a combination of these positions.

{{Main|Romanization of Thai}}

There is no universally applied method for transcribing Thai into the Latin alphabet. For example, the name of the main airport is transcribed variably as Suvarnabhumi, Suwannaphum, or Suwunnapoom. Guide books, textbooks and dictionaries follow different systems. For this reason, many language courses recommend that learners master the Thai script.{{cite book |last1=Pronk |first1=Marco |title=The Essential Thai Language Companion: Reference Book: Basics, Structures, Rules |date=2013 |publisher=Schwabe AG |isbn=978-3-9523664-9-3 |page=v |url=https://books.google.com/books?id=ctZBDwAAQBAJ&pg=PR5 |language=en |quote=learn the Thai alphabet as early as possible, and get rid of romanized transcriptions as soon as you can}}{{cite book |last1=Juyaso |first1=Arthit |title=Read Thai in 10 Days |date=2015 |publisher=Bingo-Lingo |page=xii |url=https://books.google.com/books?id=r6dcEAAAQBAJ&pg=PR12 |language=en |quote=There have been attempts by Thai language schools to create a perfect phonetic system for learners, but none have been successful so far. ... Only Thai script is prevalent and consistent in Thailand.}}{{cite book |last1=Waites |first1=Dan |title=CultureShock! Bangkok |date=2014 |publisher=Marshall Cavendish |isbn=978-981-4516-93-8 |chapter-url=https://books.google.com/books?id=gh0dAwAAQBAJ&pg=PT186 |language=en |chapter=Learning the Language: To Write or Not to Write |quote=you're far better off learning the Thai alphabet}}{{cite book |last1=Cooper |first1=Robert |title=CultureShock! Thailand: A Survival Guide to Customs and Etiquette |date=2019 |publisher=Marshall Cavendish |isbn=978-981-4841-39-9 |chapter-url=https://books.google.com/books?id=o7SaDwAAQBAJ&pg=PT209 |language=en |chapter=Learning Thai: Writing Thai in English |quote=take a bit of time to learn the letters. The time you spend is saved many times over when you begin to really learn Thai.}}

Official standards are the Royal Thai General System of Transcription (RTGS), published by the Royal Institute of Thailand,[http://www.royin.go.th/ Royal Thai General System of Transcription], published by the Thai Royal Institute only in Thai and the almost identical {{nowrap|ISO 11940-2}} defined by the International Organization for Standardization. The RTGS system is increasingly used in Thailand by central and local governments, especially for road signs.{{citation|url=http://www.ooh5.go.th/book/CA/CA01.pdf |archive-url=https://web.archive.org/web/20171115222340/http://www.ooh5.go.th/book/CA/CA01.pdf |archive-date=2017-11-15 |url-status=live|at=Appendix ง|language=th|title=Handbook and standard for traffic signs}} Its main drawback is that it does not indicate tone or vowel length. As the system is based on pronunciation, not orthography, reconstruction of Thai spelling from RTGS romanisation is not possible.

{{Main|Thai transliteration}}

The ISO published an international standard for the transliteration of Thai into Roman script in September 2005 (ISO 11940).[http://www.iso.org/iso/home/store/catalogue_tc/catalogue_detail.htm?csnumber=29544 ISO 11940 Standard]. By adding diacritics to the Latin letters it makes the transcription reversible, making it a true transliteration. Notably, this system is used by Google Translate, although it does not seem to appear in many other contexts, such as textbooks and other instructional media.

• Thai script
• Thai honorifics
• Thai literature
• Thai numerals
• Thai braille
• Thai typography
• Comparison of Lao and Thai

{{Notelist}}

{{Reflist}}

{{refbegin}}

• {{lang|th|อภิลักษณ์ ธรรมทวีธิกุล และ กัลยารัตน์ ฐิติกานต์นารา.}} 2549. {{lang|th|การเน้นพยางค์กับทำนองเสียงภาษาไทย}} (Stress and Intonation in Thai) {{lang|th|วารสารภาษาและภาษาศาสตร์ ปีที่ 24 ฉบับที่ 2 (มกราคม – มิถุนายน 2549) หน้า 59–76.}} {{ISSN|0857-1406}}.
• {{lang|th|สัทวิทยา : การวิเคราะห์ระบบเสียงในภาษา. 2547. กรุงเทพฯ : สำนักพิมพ์มหาวิทยาลัยเกษตรศาสตร์.}} {{ISBN|974-537-499-7}}.
• Diller, Anthony van Nostrand, et al. 2008. The Tai–Kadai Languages. {{ISBN|978-070-071-457-5}}.
• Gandour, Jack, Tumtavitikul, Apiluck and Satthamnuwong, Nakarin. 1999. Effects of Speaking Rate on the Thai Tones. Phonetica 56, pp. 123–134.
• Li, Fang-Kuei. A handbook of comparative Tai. Honolulu: University Press of Hawaii, 1977. Print.
• Rischel, Jørgen. 1998. 'Structural and Functional Aspects of Tone Split in Thai'. In Sound structure in language, 2009.
• Tumtavitikul, Apiluck, 1998. The Metrical Structure of Thai in a Non-Linear Perspective. Papers presented to the Fourth Annual Meeting of the Southeast Asian Linguistics Society 1994, pp. 53–71. Udom Warotamasikkhadit and Thanyarat Panakul, eds. Temple, Arizona: Program for Southeast Asian Studies, Arizona State University.
• Apiluck Tumtavitikul. 1997. The Reflection on the X′ category in Thai. Mon-Khmer Studies XXVII, pp. 307–316.
• {{lang|th|อภิลักษณ์ ธรรมทวีธิกุล}}. 2539. {{lang|th|ข้อคิดเกี่ยวกับหน่วยวากยสัมพันธ์ในภาษาไทย}} วารสารมนุษยศาสตร์วิชาการ. 4.57–66. {{ISSN|0859-3485}} {{eISSN|2673-0502}}.
• Tumtavitikul, Appi. 1995. Tonal Movements in Thai. The Proceedings of the XIIIth International Congress of Phonetic Sciences, Vol. I, pp. 188–121. Stockholm: Royal Institute of Technology and Stockholm University.
• Tumtavitikul, Apiluck. 1994. Thai Contour Tones. Current Issues in Sino-Tibetan Linguistics, pp. 869–875. Hajime Kitamura et al., eds, Ozaka: The Organization Committee of the 26th Sino-Tibetan Languages and Linguistics, National Museum of Ethnology.
• Tumtavitikul, Apiluck. 1993. FO – Induced VOT Variants in Thai. Journal of Languages and Linguistics, 12.1.34 – 56.
• Tumtavitikul, Apiluck. 1993. Perhaps, the Tones are in the Consonants? Mon-Khmer Studies XXIII, pp. 11–41.
• Higbie, James and Thinsan, Snea. Thai Reference Grammar: The Structure of Spoken Thai. Bangkok: Orchid Press, 2003. {{ISBN|974-8304-96-5}}.
• Nacaskul, Karnchana ({{lang|th|ศาสตราจารย์กิตติคุณ ดร.กาญจนา นาคสกุล}}) Thai Phonology, 4th printing. ({{lang|th|ระบบเสียงภาษาไทย, พิมพ์ครั้งที่ 4}}) Bangkok: Chulalongkorn Press, 1998. {{ISBN|978-974-639-375-1}}.
• Nanthana Ronnakiat ({{lang|th|ดร.นันทนา รณเกียรติ}}) Phonetics in Principle and Practical. ({{lang|th|สัทศาสตร์ภาคทฤษฎีและภาคปฏิบัติ}}) Bangkok: Thammasat University, 2005. {{ISBN|974-571-929-3}}.
• Segaller, Denis. Thai Without Tears: A Guide to Simple Thai Speaking. Bangkok: BMD Book Mags, 1999. {{ISBN|974-87115-2-8}}.
• Smyth, David (2002). [https://web.archive.org/web/20141129015343/https://www.uta.edu/faculty/cmfitz/swnal/projects/CoLang/courses/Ped_Grammar/thai_grammar.pdf Thai: An Essential Grammar], first edition. London: Routledge.
• Smyth, David (2014). Thai: An Essential Grammar, second edition. London: Routledge. {{ISBN|978-041-551-034-9}}.
• {{Citation

|last1=Tingsabadh

|first1=M.R. Kalaya

|last2=Abramson

|first2=Arthur

|year=1993

|title=Thai

|journal=Journal of the International Phonetic Association

|volume=23

|issue=1

|pages=24–28

|doi=10.1017/S0025100300004746

|s2cid=249403146

}}

{{refend}}

• Inglis, Douglas. 1999. [https://www.academia.edu/7152881/Lexical_conceptual_structure_of_numeral_classifiers_in_Thai-Part_1 Lexical conceptual structure of numeral classifiers in Thai-Part 1]. Payap Research and Development Institute and The Summer Institute of Linguistics. Payap University.
• Inglis, Douglas. 2000. [https://www.academia.edu/7152883/Grammatical_conceptual_structure_of_numeral_classifiers_in_Thai-Part_2 Grammatical conceptual structure of numeral classifiers in Thai-Part 2]. Payap Research and Development Institute and The Summer Institute of Linguistics. Payap University.
• Inglis, Douglas. 2003. Conceptual structure of numeral classifiers in Thai. In Eugene E. Casad and Gary B. Palmer (eds.). Cognitive linguistics and non-Indo-European languages. CLR Series 18. De Gruyter Mouton. 223–246. {{ISBN|978-311-017-371-0}}

{{External links|section|date=June 2015}}

{{InterWiki|code=th}}

{{Wikiquote|Thai proverbs}}

{{Wikivoyage|Thai phrasebook|Thai|a phrasebook}}

{{Prone to spam|date=July 2012}}

• [http://www.phon.ucl.ac.uk/home/sampa/thai.htm IPA and SAMPA for Thai]
• [http://hdl.handle.net/10106/6079 Consonant Ear Training Tape]
• [http://hdl.handle.net/10106/9760 Tones of Tai Dialect]

; Glossaries and word lists

• Thai phrasebook from Wikivoyage
• Thai Swadesh list of basic vocabulary words (from Wiktionary's [http://en.wiktionary.org/wiki/Appendix:Swadesh_lists Swadesh-list appendix])

; Dictionaries

• [http://english-thai-dictionary.com/ English–Thai Dictionary]: English–Thai bilingual online dictionary
• [http://www.royin.go.th/dictionary/index.php The Royal Institute Dictionary], official standard Thai–Thai dictionary
• [http://www.thai-language.com/dict/ Thai-English dictionary]
• [http://www.thai2english.com/ Thai2english.com]: LEXiTRON-based Thai–English dictionary
• [http://www.cymraeg.ru/daoulagad.html Daoulagad Thai]: mobile OCR Thai–English dictionary
• [https://thaidictproject.wixsite.com/website/ Thai dictionaries for Stardict/GoldenDict] – Thai – English (also French, German, Italian, Russian, Chinese and others) dictionaries in Stardict and GoldenDict formats
• [http://belisan-volubilis.blogspot.com/ Volubilis Dictionary] VOLUBILIS (Romanized Thai – Thai – English – French): free databases (ods/xlsx) and dictionaries (PDF) – Thai transcription system.

; Learners' resources

• [http://www.thai-language.com/ thai-language.com] English speakers' online resource for the Thai language
• [http://www.ipl.org/div/hello/thai.html Say Hello in the Thai Language]
• [http://www.thai-notes.com/FSITLC FSI Thai language course] (Formerly at thailanguagewiki.com)
• [https://web.archive.org/web/20110717055101/http://www.seasite.niu.edu:85/thai/spokenthai/ Spoken Thai] (30 exercises with audio)

{{Thailand topics}}

{{Languages of Thailand}}

{{Tai-Kadai languages}}

{{Authority control}}

Category:Analytic languages

Category:Isolating languages

Category:Languages attested from the 13th century

Category:Languages of Thailand

Category:Languages written in Brahmic scripts

Category:Stress-timed languages

Category:Subject–verb–object languages