--You just think of yourself! You kept me waiting for at least three hours．–I am sorry that you________think so.

Cars play an important role in modern life, but they_______also cause many problems like air pollution．

—What a great cook your sister is! —Yeah! We ______ never have enough of her cookies．

My father ______ you a lift, even if he didn’t plan to take that way．

John ___ be a basketball player.He’s much too short.

See who’s there! ____ it be Mary?

He ___ be in the garden.He must be in the room.‘

He ___ at the meeting this morning.He was in hospital at the time.

It's dark, Mum ___ be waiting for my return.

I ___, but I didn't think you were serious.

 Madonna ____a straight A student,but it was dancing that she was really crazy about.   

We were all surprised when he made it clear that he ___ office soon.

--Don't be so disappointed.I’m sure that you can do better in the next exam. --Yes, but I ____ this time.

We _____ last night,but we went to appreciate the flowerbeds and streetlights in Tian’anmen Square instead.

—Did you arrive here this morning?—Yes,it was at nine o’clock ____we came here.

You did not go to the party yesterday, or I ___ you.

As a graducate in computer science, he ___ to work out the problem.

If you want to borrow a football after school, your student card ___ here.

You ___ me, but since you have,I’ll keep it secret from others.

If you have something important to do, you ___ waste any time.