thus: i- + kwis + -u, the verb stem loses its only vowel, resulting in the form ikwsu "he/she/it ate". Sometimes omitting different vowels may lead to alternative results. Adding the past tense suffix -u to the verb stem maling "kill", i.e. maling + -u, may give either mlingu or malngu "killed".

There are also cases of vowel alternation in morphemes (e.g. the first-person subject prefix may appear as n-, ni- or na-) and lexical stems (thus the stem aakar "stay" may appear in the forms aak'ir-i