专升本英语语法单项选择25个题差不多一个语法点一个题，所以我们要一个一个语法点攻破，今天来和小编一起学习情态动词，这可是必考的哦！
情态动词考点：
Can, could
May, might
Must/have to
Need
Dare
Will/would
Shall/should/ought to
考点一： Must的否定回答
在回答must引起的问句时，如果是否定的答复，可用don’t have to或needn’t(不必) ，但不能用mustn’t(一定不，必须不，不允许，不得) 。如：
—Must I clean the dining room at once? 我必须马上打扫餐厅吗？
—Yes, you must. 是的，你必须马上打扫。
—No, you don’t have to (=needn’t) . 不必啦。
You mustn’t smoke in the office. 你不得在办公室抽烟。
考点二：must表肯定猜测：
Must表示推测时，只能用于肯定句中
must do 对一般时的肯定推测
must be doing 对现在的动作进行肯定推测
must have done 对过去发生的事情作出的肯定判断
They have bought a new car. They must have a lot of money.
He must be reading novels now.
The road is wet. It must have rained last night.
考点三：can’t/could’t表否定推测
考点四：need doing sth=need to be done
The flowers need watering.=The flowers need to be watered.
The house needs painting.=The house needs to be painted.
延伸：want, request doing sth=want/request to be done
考点五：need/dare既可做实意动词，也可做情态动词。实意动词用在肯定句中（need/dare to do sth），情态动词用在否定和疑问句中(need/dare do sth )。
Dare you walk through the forest at night?
You needn’t return the book now.
He needs to go there himself.
三．情态动词练习
1.--- She looks very happy. She ______ have passed the exam.
—I guess so. It’s not difficult after all.
A. should B. could C. must D. might
2. You ______ be hungry already , you had lunch only two hours ago!
A. wouldn’t B. can’t C. mustn’t D. needn’t
3.—I’m sorry. I _________at you the other day.
—Forget it. I was a bit out of control myself.
A. shouldn’t shout
B. shouldn’t have shouted
C. mustn’t shout
D. mustn’t have shouted
4. Thank you for all your hard work last week. I don’t think we ______ it without you.
A. can manage B. could have managed
C. could manage D. can have managed
5. —There were already fi ve people in the car but they managed to take me as well.
—It ________ a comfortable journey.
A. can’t be B. shouldn’t be
C. mustn’t have been D. couldn’t have been
6. The boss has given everyone a special holiday, so we —go to work tomorrow.
A. can’t B. mustn’t
C. needn’t D. shouldn’t
7. Since the road is wet this morning, ______ last night.
A. it must have rained B. it must rain
C. it must be raining D. it must have been rained
8. As teachers we should concern ourselves with what is said, not what we think ______.
A. ought to be said B. must say
C. have to be said D. need to say
9.You ______ all those calculations. We have a computer to do that sort of thing.
A. must not have done B. should not have
C. can not have done D. needn’t have done
10.With all this work on hand, he ______ to the cinema last night.
A. mustn’t go B. wouldn’t go
C. oughtn’t go D. shouldn’t have gone
