The orthography is mostly phonemic, although the characters ae, oe, ue, and ’ represent allophonic variations: the three vowel digraphs are the product of vowel coalescence, and the apostrophe represents the glottal stop, a syllable-final variant of /k/.
Although Kom has eight phonetic tones,[3] only two are marked in writing: the low tone [˨] is written with a grave accent (◌̀) over the vowel (e.g. kàe [kæ̀] "four"), and the high-low falling tone [˦˨] is written with a circumflex (◌̂) over the vowel (e.g. kâf [kâf] "armpit").[5]
References
^Kom at Ethnologue (18th ed., 2015) (subscription required)