
【易错点睛】
1. 表示必须
此时可用于肯定句、否定句或疑问句,用于否定句时,mustn’t的意思是“一定不要、不能”。如:You must finish the work tonight. 你必须今晚完成这项工作。
Adverbs mustn’t be put between the verb and the object. 副词不能放在动词和宾语之间。
2. 表示推测
意为“一定是”,通常只用于肯定句,表示有把握的肯定推测。
如:Jane’s light is on. She must be at home. 简的房间里开着灯。她一定在家。
3. must与have to的区别
| must侧重于说话者的主观看法,认为有必要或有义务去做某事 | Everyone must keep the law. 人人都要守法。 |
| have to 则重于客观需要,含有“不得不”“被迫”之意 | The last train has gone. We’ll have to walk home. 最后一班车已经开了,我们得走回家了。 |
如:You will have to show your papers at the gate. 在大门口你得出示证件。
【典型错题】
If you know nothing about the famous program called Where are we going, dad?, you _____ be living in a box!
A. would B. can C. must D. need
【错因分析】本题的关键是对语境的理解,对句意的把握会直接影响能否正确判断空格处所缺情态动词的意思。其次,如果没有掌握选项中四个情态动词的用法,也会影响正确作答。
【思路点拨】首先要理解题干中句子的意思,然后弄清楚四个选项中情态动词的用法,再结合句意判断空格处要表达的是肯定推测“一定是”,再结合选项得出正确答案。
【正确答案】正确答案为C。句意:如果你对《爸爸去哪儿了》这个著名的节目一无所知,那你一定是生活在盒子里。根据上文提示此空是表示肯定的推测,“一定是”要用情态动词must,故选C。
【中考链接】
1. (2018 重庆)You _______ stop when the traffic lights(交通灯) turn red.
A. can't B. may C. must D. needn't
【答案】C
解析:句意:交通灯变红时你______停车。A. can’t不能,B. may可能,C. must必须,D. needn't不必,根据句意,答案选C。
2. (2017 福建) —Mum, may I go swimming now?
—Yes, dear, but remember that you ______ go with your dad.
A. may B. can C. must
【答案】C
解析:句意:——妈妈,我现在可以去游泳吗?——是的,亲爱的,但是记住你必须和你爸爸一起去。may可以;can可能;must必须。根据语境可知这里用must。故选C。
3. (2017 黔西南州)—Must I leave now? It’s still raining hard outside.
—No, you ______.You can wait till the rain stops.
A. don’t have to B. couldn’t C. can’t D. shouldn’t
【答案】A
解析:句意:——我必须现在离开吗?外面还在下雨。——不,你不必.你可以等到雨停。don't have to不必;couldn't不能;can’t不能;shouldn’t不应该。在回答以must开头的一般疑问句时,肯定回答用Yes, sb. must,否定回答用No, sb. needn't或don't have to,结合句意,答案选A。
【闯关提分训练】must和have to
1. —Can you go shopping with us this afternoon?
—Sorry, I can’t. I ______ look after my little sister.
A. can B. may C. have to
2. —May I smoke here?
—No, you ________. This is a no-smoking room.
A. needn’t B. mustn’t C. need D. wouldn’t
3. Someone is knocking at the door. It ______ be my mother. It’s time for her to be back.
A. can B. may not C. must D. mustn't
4. You _____ take me to the station. My brother’s taking me.
A. can’t B. mustn’t C. shouldn’t D. don’t have to
5. — Sorry, Miss Liu. I left my workbook at home. Must I hand it in(上交它) today?
— No, you ______. You ______ bring it here tomorrow.
A. mustn’t; should B. can’t; must C. mustn’t; may D. needn’t; can
6. —Excuse me, sir, visiting hours(探视时间) are over. You _____ leave.
—Pardon me(对不起), nurse. I didn’t hear the bell(铃声).
A. may B. can C. must D. need
7. The children ______ play basketball on the road.
A. can’t B. can C. mustn’t D. must
8. You ______ go and see a doctor at once because you got a fever(发烧).
A. can B. must C. dare D. would
9.—Mum, must I finish the homework now?
—No, you ______.You can do it after supper.
A. needn't B. mustn't C. can't D. may not
10. (2018 盐城一模)Sorry! I can't follow you. I ____ finish my homework first.
A. can B. may C. must D. could
11. (2018·济南三模) —Must I answer the question in English?
—No, you _______.
A. can't B. mustn't C. needn't D. shouldn't
12. Yesterday it rained heavily when school was over. We _____ stay in our classroom
A. must B. should C. had to D. need
13. I can’t go with you. I ______ stay at home until my parents come back.
A. can B. may C. must D. could
14.—Must I finish the work today?
—No, you ______. But you ______ finish it next Monday.
A. mustn’t; must B. needn’t; must C. mustn’t; could D. needn’t; could
15. —______ you ______ wear your sports shoes for P.E. class?
—Yes, we do.
A. Have; to B. Do; have C. Do; have to D. Does; have to
16. —May I go out now, Dad?
—Well, you _________ finish your school work first.
A. can B. may C. need D. must
17. —Why can’t Nancy come to your party?
—Because she ______ do her homework.
A. can B. can’t C. has to D. doesn’t have to
18. (2018 河西区一模) Mike _____ finish the work at once. He can finish it tomorrow.
A. must B. have to C. shouldn't D. doesn't have to
19. We shouldn't arrive late for class. We ______ be on time.
A. must B. may C. could D. can
20. It is in the library. You __________ talk loudly.
A. may not B. wouldn't C. needn't D. mustn't
参:
1.C 2.B 3.C 4. D 5. D 6. C 7. C 8. B 9. A 10. C
11. C 12. C 13. C 14. B 15. C 16. D 17. C 18. D 19. A 20. D
