The tap /ɾ/ varies freely between [ɾ] or a retroflex [ɻ].
[ʃ] is heard as an allophone of /tʃ/ among young speakers.[2]
/b/ is heard as [p] in word-final position.
/k/ may vary between a voiced [ɡ] or [k] when in between a high and non-high vowel.[3]
The back-velar /k̠/ may also be heard freely as uvular [q], and may vary between a stop or fricatives [k̠], [x̠] or voiced [ɡ̠], [ɣ̠] when preceded and followed by /a/ or /o/.[3]
Sounds /i, u, e, o/ may have lax allophones as [ɪ, ʊ, ɛ, ɔ] in closed syllables.
Vowels /e, o/ may have a lax allophone of [ə] when following other vowels.
/a/ may be heard as [æ] when preceding a velar nasal /ŋ/ in free variation with [a].[2]
Morphology
Pronouns and person markers
One remarkable feature of the pronoun system of Kairiru is that it appears to have lost the distinction between first-person inclusive and exclusive pronouns throughout its affix paradigms, but then recreated inclusive forms in its independent pronouns by combining first-person and second-person forms along the lines of Tok Pisinyumi (< yu + mi). The inclusive-exclusive distinction is almost universal among Austronesian languages but generally lacking in Papuan languages.
^ abWivell, Richard (1981). Kairiru grammar. University of Auckland.
^ abRoss, Malcolm (2002). Kairiru. In John Lynch and Malcolm Ross and Terry Crowley (eds.), The Oceanic Languages: Routledge: London and New York. pp. 204–215.
Wivell, Richard (1981). Kairiru grammar. M.A. thesis, University of Auckland.