a few Na-Dené questions

 working on Conlang-17...a Na-Dené member, or at least based on that family.

I managed to find a few Na-Dené websites (primarily, though not entirely,
focused upon Navaho)...but it didn't seem to mention how members of that
language family handle possessives.

ie, in Kaskan, _dene dzage_ means _people's language_.

which part of the words is changed to produce any of the following?:
_people language_
_peoples' language_

 *curious*

 thanks.