Aspiration: three kinds of p and t
English tells b from p mainly by voicing, and adds a puff of air (aspiration) to p, t and k at the start of a word without anyone noticing. Thai uses that puff as a separate contrast. For p and t it has three sounds where English has two:
| Kind | Lips | Tongue tip | Back of the tongue | English example |
|---|---|---|---|---|
| Voiced | บ b | ด d | none | bin, din |
| Unaspirated | ป p | ต t | ก k | spin, stop, skin |
| Aspirated | พ ผ ph | ท ถ th | ค ข kh | pin, top, kin |
So บา, ปา and พา are three different syllables, as are ดา, ตา and ทา. The unaspirated row is the hard one: English has those sounds only after s. English speakers tend to hear ป as b and ต as d, and to say them with a puff of air, which turns ปา (to throw) into พา (to take along). The same split runs through the ch sounds: จ is unaspirated, ฉ and ช aspirated.
Sounds one language has and the other lacks
| In Thai, not in English | In English, not in Thai |
|---|---|
| Unaspirated p, t, k, ch at the start of a word: ป ต ก จ | Voiced g, v, z and j, as in “go”, “van”, “zoo”, “jam” |
| ng at the start of a word: งู nguu, snake | The th of “thin” and “this” |
| A glottal stop before a vowel (อ) and after a short one | sh and zh, as in “ship” and “vision” |
| The vowels อึ /ɯ/ and เออ /ɤ/, said with the lips spread | The reduced vowel of “about” (schwa) |
| Contrastive vowel length: เข้า khâo against ข้าว khâao | Clusters with s: “st”, “sp”, “str” |
| Lexical tones | Most final consonants: s, f, l, r, ch, v, z, sh at the end of a syllable |
Endings: six consonants, never released
A Thai syllable can end in only six consonant sounds, k, t, p, m, n and ng, plus the glides y and w. The stops k, t and p are unreleased: the mouth closes and stays closed. Many letters share these endings, so ส, ด, ช and ต at the end of a syllable all sound t, and ล, ร, ญ and น all sound n.
English loanwords show what happens to everything else. A final s becomes t, a final f becomes p, and a final l becomes n, even when the spelling keeps the English letter:
| English | Thai spelling | Said (IPA) |
|---|---|---|
| bus | บัส | /bát/ |
| golf | กอล์ฟ | /kɔ́ːp/ |
| football | ฟุตบอล | /fút.bɔːn/ |
| file | ไฟล์ | /faːj/ |
For an English speaker the habit to break is releasing final stops: say นก as nók with the k held, not “nok-h”. For a Thai speaker learning English the habit runs the other way, which is why “nice” can come out as “night” and “bill” as “bin”.
Consonant clusters
Thai allows only a few two-consonant beginnings: k, kh, p, ph and t followed by r, l or w, as in กร, กล, กว, ปร, พล, ตร. There are no clusters with s and nothing at all at the end of a syllable. English words with clusters gain a vowel in Thai: “stop” becomes สต็อป, said /sà.tɔ́p/. In everyday speech the r of a cluster is often dropped or said as l, so ปลา and ประตู can sound like “paa” and “patuu”.
Vowels: length, not just quality
What English calls long and short vowels (the vowels of “bit” and “beat”) differ mostly in quality. Thai pairs a short and a long version of the same vowel, and length alone changes the word: ฝัน fǎn (to dream) and ฝาน fǎan (to slice) are different words, and so are เข้า khâo (to enter) and ข้าว khâao (rice). Thai vowels also keep their full quality in every syllable; there is nothing like the weak “uh” English uses in unstressed syllables, so every vowel has to be said as written.
Two Thai vowels have no English match: อือ /ɯː/, an “oo” said with the lips spread in a smile, and เออ /ɤː/, close to the vowel of British “bird” without the r. Both are common, in words such as มือ /mɯː/ (hand) and เดิน /dɤːn/ (to walk).
Tones against stress and intonation
English uses pitch for the whole sentence: it rises on a question, falls at the end of a statement, and jumps on the word you want to stress. Thai uses pitch inside the word: each syllable has one of five tones, and changing it changes the word. Thai still has stress (the last syllable of a word is usually the strongest) and sentence intonation, but both work within the tones rather than overriding them. A Thai question is marked with a word such as ไหม or หรือ, not with a rise in the voice, and attitude is carried by the small particles at the end of a sentence. The prosody guide covers how this works in connected speech.
What to practise first
- The three-way contrasts: บา ปา พา and ดา ตา ทา, with a strip of paper in front of your lips.
- ng at the start of a word: งู, เงิน, งาน.
- Unreleased finals: นก, รถ, ชอบ, holding the closure.
- Length pairs, then tone pairs, in that order: length is easier to hear, and it carries just as much meaning.