Apu tshissenimak tshetshi uitsheuakue (nana) Punissa ekusseniti.
I don’t know whether he (absent) went fishing with Puniss.

This form is used when there is doubt about the event described by the verb. We do not know whether this event is happening or not.

Apu tshissenimimaki Tshan utauia tshetshi tashkaitshenikue e peikussiniti.
I don’t know whether John’s father can split the wood by himself.

The changed form forms another conjugation (#14b).

Link to the conjugation guide.