3.“情态动词+have done”的用法 ：
must have done表示对过去事情的肯定推测。
can't / couldn't have done表示对过去所发生的事情所做的否定推测。 may have done表示过去所发生的事情作可能性推测。
might / could have done表示对过去所发生的事情作可能性推测，或者表示本来可以做而事实上未做的事情。
should / ought to have done表示本应该做的事情而事实上未做 needn't have done表示做了本不应该做的事情。
巩固练习：
1. We demanded that we _______ of any change in the plan. A. informed B. would be informed A. has
B. have B. turn
C. had
C. be informed D. had been informed D. having
D. would turn
2. It’s necessary that he _______ a recognized qualification. 3. It's high time we ______ our attention to this problem. A. turned
C. had turned
4. If only you __________ him what I said! Everything would have been all right. A. didn't told B. hadn't told C. would not tell D. would have not told 5. He must have had an accident, or he_______ here then. A. would have been
B. had been C. should have been
D. could be
6. You ________ to town to see the film last week. It will be on TV tomorrow. A. needn't go B. should not go
C. had better not go D. needn't have gone
7. How I wish every family ___ a large house with a beautiful garden! A. has B. had C. will have D. had had
8. When a pencil is partly in a glass of water, it looks as if it ________. A. breaks B. has broken C. were broken D. had been broken 9. Jane’s pale face suggested that she ___ ill, and her parents suggested that she _____ a medical examination.
A. be, should have B. was, have C. should be, had D. was, has 10. The bus driver insisted that he _____ at normal speed and therefore _____ for the child’s death.
A. drive, not answer B. was driving, shouldn’t answer C. should drive, shouldn’t have answered D. drove, shouldn’t answer
改错练习：
One day my uncle had been riding a horse in rain when he reached a small restaurant. Wet and coldly, and he wanted to warm himself very much. However, the restaurant was too crowded with people that he could not get near the fire. “Taking some fish to my horse!” he called out to the waiter. “Sorry, sir. But a horse didn’t eat fish!” the waiter answered. “Never mind, just do as I tell you,” my uncle said. The crowd of people felt surprising at the strange order. To see a horse eat fish, all of whom ran out. Having the whole room to himself, my uncle sat down besides the fire and began warm himself.