Tessian language

Phonology
The Kossian language has a deceptively simple phonology with only three vowel phonemes /a i u/ and ten consonant phonemes /n p b t d k g s l r/.

Ablaut
The Kossian language features a system of apophony similar to the system found in Proto-Indo-European, which is therefore referred to as 'Kossian ablaut'. Kossian ablauts are regular vowel alternations within a morpheme due to the addition of certain suffixes. The three phonemic vowels of the Kossian language /a i u/ can exist in three stages of ablaut, referred to as first, second and third grade, respectively. The ablauts are: