If you're living and teaching in an English-speaking country (and it looks like you might be), I would teach some survival words, expressions and questions.
Teach the types of things you think your students will absolutely need on a day-to-day basis, and some other basic things. For example:
My name is___________.
My address is ___________.
My phone number is ___________.
Also, phrases of greeting and saying goodbye.
The rest will depend on the specifics of your students' situations. Are they adults, kids, spouses, parents, etc.