ki'u _BAI cmavo

krinu modal, 1st place (justified by) justifiably; because of reason ...

On affix form:

krinu: x₁ (event/state) is a reason/justification/explanation for/causing/permitting x₂ (event/state).

In notes:

ja'onai (comp!): discursive/evidential: after all...
ki'au (exp!): evidential: I reason - I think impulsively.
ko'au (exp!): kosmu modal, 1st place with purpose...
lu'ei (exp!): convert a grammatical quotation to a tanru unit; x₁ expresses/says the quoted text for audience x₂ via expressive medium x₃.