Page 186 - The International Journal of the Royal Society of Thailand Vol.XIII-2021

The International Journal of the Royal Society of Thailand
Volume XIII – 2021

7. Vowels

Thai vowels are classified in 3 groups as follows:

7.1 Monophthong

Monophthongs are divided into 9 pairs of short-long sounds as follows:

Table 11: Thai Monophthongs

Long Short

i  u i  u

e  o e  o

 a   a 

All the 18 monophthongs are written in these vowel forms as follows:

Table 12: Thai vowel forms

Long Short

-ี -ื -ู -ิ -ึ -ุ

เ- เ-อ โ- เ-ะ เ-อะ โ-ะ

แ- -า -อ แ-ะ -ะ เ-าะ

The complexity of the Thai writing system lies in the fact that some vowels
will change form with the addition of a final consonant as follows:

176 The Thai Writing System: Reasons behind Its System