A couple of interviews my son did was testing to see if he can answer or know what were being asked. My son did not speak much and mostly pointed.
Some questions asked were:
-what's your name
-how old are you
-if one of the parents sitting in, they asked him who I was
-pushing a car to mummy, to the teacher
-putting back toys in the box
-3 items were shown, e.g an orange, a cup and a ball, teacher asked him to give the items to her
-pictures of a bed, sofa, fridge and TV were placed infront of him, teacher asked him to point to the items asked
-body parts such as eyes, nose and mouth
I think you should not stress out too much over the interviews - the above questions were everyday things we taught our son in both english and cantonese and they do pick up very easily. He got rejected by one kindy and not sure whether or not this was because he did not say much although he did get all the other things correct. My son can only say single and double words -am waiting the day he can have a conversation with us. Don't know how the kindy used what to decide on accepting or rejecting. There were over 1000 applications for 400 places!