Vowels in Thai all come in 2 lengths; short and long.

Every vowel has a long and short version. The only difference is that for the long vowels you say the vowel a bit longer.
For instance, say a word is “hat” and another one is “haat”. You would just hold the “a” sound in “haat” for a tiny bit longer. Literally, like a ~1/4 of a second longer.
Let’s see some examples of the long vowels and the short vowels in Thai. (This is not a comprehensive list).
| Long Vowel | Short Vowel |
|---|---|
| เธฒ (aa) | เธฑ (a) |
| เธท (eeuu) | เธถ (eu) |
| เธต (ee) | เธด (i) |
| เธน (oo) | เธธ (u) |
| เธฒเธข (aai) | เธฑเธข (ai) |
| เธฒเธข (aai) | เน (ai) |
Why is vowel length in Thai important?
Pronouncing the words with the correct vowel length is important because otherwise, you might be saying a completely different word.
Also, the length of the vowels might affects the tone the word will have. You will see examples below.
Examples of short and long vowel length words in Thai
Let me explain the difference in vowel length with some examples in Thai.
- เธเธฑเธ (bpร t) and เธเธฒเธ (bpร at). เธเธฑเธ (bpร t) means to brush away and as you can see it uses the short form of the vowel.
เธเธฒเธ (bpร at) means to sweep away and it uses the long version. - เธซเธฑเธ (hร t) and เธซเธฒเธ (hร at). เธซเธฑเธ (hร t) means to practice and uses the short version of the vowel.
เธซเธฒเธ (hร at) means beach and uses the long version of the vowel. - เธเธฒเธข (paai) and เธ เธฑเธข (pai). เธเธฒเธข (paai) uses the long version of the vowel and means a paddle.
เธ เธฑเธข (pai) uses the short version and means danger.
In the above cases, the only difference was the long and short version of the vowels. However, depending on the tone rules, a change of length in the vowel can also change the tone of the syllable.
- เธฅเธฑเธ (lรกk) and เธฅเธฒเธ (lรขak). เธฅเธฑเธ (lรกk) uses the short form of the vowel and this means to steal (also the tone is high).
เธฅเธฒเธ (lรขak) uses the long-form and means to drag (and the tone is falling).
I hope you now understand vowel length in Thai and the difference between the short and long vowel length.
