Difference between oe, oer, and oeru?

[NaviMcCall94]

Kalxì ma tsmuk.  I am a fairly new speaker and I was wondering what is the difference between oe, oeru, and oer, and/or when you use which.
Iray ulte Eywa Ngahu ma tsmuk!

[kewnya txamew'itan]

What you've brought up are the different cases of oe.

The full list (not including adpositions which make even more or the topical because that is very complicated) is:

oe
oel
oet
oeti
oer
oeru

oet and oeti mean the same, they're just different variants, pick whichever sounds better in your sentence.

Same with oer and oeru, they mean the same, just different forms.

The blank for is used in intransitive verbs (verbs where there is no object, nothing being affect like "to be" or "to go"), it is also used with adpositions as in oehu/hu oe which means "with me".

The following sentence should explain the others reasonably:

X tìng Y Z (using an English word order which I wouldn't normally do)

If I am doing the giving (if I am person X) I am the subject of a transitive verb (there is an object, the thing I'm giving) and so I'd use oel which is called the ergative case.

If I am person Y and am being given then I am the direct object of the verb and take the accusative case and I'd use oet(i).

If I am person Z, and person Y is given to me I am the indirect object and take the dative case so I'd use oer(u). Datives are normally shown in English either by appearing before the direct object "he gave me the bow" or after it with the preposition "to" in front of it "he gave the bow to me".

Si verbs also use the dative case for their semantic direct objects because syntactically they can't take direct objects, for example instead of saying "he betrayed me" which you'd expect to be "poanìl kavuk si oeti", you'd actually use "poan kavuk si oeru" (this also means that the subject uses its blank form not the ergative case).