Vowels

There are four. Romanized spelling and phonetic values are given below.

i [i]	u [u]
a [æ]	o [ɔ]

Diphthongs and triphthongs occur but are subject to the restriction that linearly adjacent vowels must be adjacent on the vowel square: thus iu, oa, iao and so forth occur, but not *io or *ua.