---Could you tell me when your father___back?---I’m not sure now. but when he ___next week, I’ll tell you.
— Whose room is bigger, Li Pin’s or ______? —His room. But my room is nicer!
—Is _______ here ? —Bob is not here.
—What are you going to give your mother for her birthday? —I’m not sure. But I’ll buy her _______.
— Who will go to the _____ for teeth cleaning with you, Mark? — My father.
If you play sports ______a living, your job will sometimes be very dangerous. A. for B. at C. by