The teacher is already standing here. Do you know when she ______?

We are sure one day the air in Beijing will be much ______ than today.

It is a common practice in the USA that one needs to make a(n) ___ before seeing a doctor.

Can you tell me Kitty’s address.－I don’t know, either. But I’ll tell you her address as soon as she ______ to me.

What are you looking for? —I’m looking for the book _____ I bought yesterday.[ ]