What’s the matter _____ you?A. with B. on C. in
-- Would you please __________your radio a little? I can hardly go to sleep.-- Oh, sorry.
There __________ some children in the painting room. They are studying painting.
–Have you ever been Canada? --__________.But I hope to go there one day!
--Would you mind opening the window? It’s too hot.--__________.
—Listen ! Helen is singing in the next room.—It __________ be Helen. She is in Tianjin now.