________, someone knocked at the door.

A. Having finished my homework　　    B. While I was doing my homework

C. Doing my exercises　　　　　　　　　　    D. When doing my exercises

Have you asked her for the reason ________ may explain for her absence.

A. what　　　　　　　　 B. that　　　　　　　　   C. why　　　　　　　　  D. because

The cost of sales makes up a large part of the prices that ________.

A. are paid for all products　　　　　　　　  B. all products are paid

C. for which all products are paid　　    D. for all products paid

When ________ the education system of China and Japan, the professor made no answer.

A. being asked to compare　　　　　　　　  B. asking him to compare

C. asked to compare　　　　　　　　　　　　   D. asked him to compare

I feel silly in these clothes. Everyone will ________ me.

A. worry about　　  B. make fun of　　　　　　  C. get rid of　　　　   D. take interest in

To everyone’s surprise, the fashionable young lady ________ to be a thief.

A. found out　　　　  B. proved out　　　　 C. put out　　　　　　　　　　 D. turned out

—Isn’t it surprising that such a good football team ________ have failed to enter the World Cup Final?

—Yes, anything is possible on the football field.

A. would　　　　　　   B. might　　　　　　    C. must　　　　　　　　 D. should

As is natural, a man as old as he ________ be very forgetful.

A. can　　　　　　　　   B. must　　　　　　　　 C. should　　　　　　   D. would

You ________ pay too much attention to your reading skill, as it is so important.

A. cannot　　　　　　　　　　 B. should　　　　　　   C. must　　　　　　　　 D. needn’t

—David, it’s Frank. Do you have a few minutes? I need to see you.

— ________. But I hope“a few minutes”don't turn into an hour.

A. I’m afraid not　　　　　　　　　　　　　　    B. It doesn’t matter

C. I don’t think so　　　　　　　　　　　　　　  D. I guess so.