I am a private piano teacher. I recently accepted a student who has only been living in the US for a couple weeks and does not know English. Her mother sits next to us during the lessons and translates.  I struggle particularly with getting the student's input. Example exchange:

> Me, to student: This notation is complicated. What do you think he
> wants you to do?
> 
> Mother, to me: Actually, I don't even understand what's going on here.
> 
> Me, to mother: Could you please ask her what she thinks? I'd like to
> see how she handles it.

Whereupon the mother translates, and the student plays the passage in question, giving me no way to know if she's being imprecise, or if she doesn't understand the notation.

What can I do to communicate effectively through the translator.

They are from China, if it makes a difference.