______ there is no water left on the earth —I really don’t know.

I hear that Tom can’t afford his schoolingthis fall.— _____, let’s do something for him.

Has he returned from Canada_________— Yes, he’s _________ come back.

Several years ago, very ______ people knew Yao Ming .But now he is well-known all over the world.

Mum, must I wash the dishes right now — No, you _________.