1、情态动词一、 can/could1. 表示“能力”，can表示现在的能力，could 表示过去的能力。例 Can you lift this heavy box?2. 表示推测，通常用于否定句，cant表示“不可能”，用于表示把握比较大的推测。例 That cant be Mary, for she is in hospital.3. 表示“请求”和“许可”(could 用来表示“请求”时，是委婉的说法，回答时一般用can)。例 -Could you please do me a favor? -Yes, I can.-Finish drawing a horse in ten minutes
2、.OK？-Sorry.It_in such a short time.A. may do B.cant be done C.must do D.neednt be done_she ride when she was three years old？A. Can B.Could C.Need D.May答案：B B二、 may/might1. may 和 might 在肯定句中表示“允许”，在疑问句中表示“请求”。might表示请求时，对其进行肯定回答用may/can, 而不用might；对于may的疑问句，肯定回答用“Yes, you may.”，否定回答用“No, you cant/mus
3、nt.”例 May I go fishing with you tomorrow? Yes, you may. /No, you cant/mustnt.2. 表示推测，意为“可能，或许”，比can的可能性小。通常不用于疑问句中。例 She may be at home today.3. may 用于祈使句中表示祝愿。例 May you be happy forever. -_I have your name，please？ -Yes，Michael.M-I-C-H-A-E-L. A.Must B.Will C.May D.Need -May I go to the cinema，dad？ -
4、No，you_.You must finish your homework first. A.mustnt B.wont C.dont D.neednt -What do you send to your sister as a Christmas gift? -I havent decided yet. I _ send her a handbag.答案：C A may 可能性 cancouldmaymight礼貌程度 mightmaycouldcan三、 must1. 表示义务、必要性、命令等，意为“必须，应该”，更强调主观态度。例 You must finish your homewor
5、k this afternoon. You mustnt smoke here.2. 表示推测。语气最为肯定，一般用于肯定句，意为“一定，准是”。例 She must be tired after such a long walk.注意：其否定形式为mustnt, 意为“不许，禁止”。若要表示“不必须，没必要”时，则用dont have to或neednt ；若表示“不可能”时，用cant.练习 The desk is not dirty.You_clean it. A.mustnt B.shouldnt C.neednt D.cant Is Jessica giving us a speec
6、h this evening? -No, it _be her. She_ to Japan. A.mustnt has gone B.mustnt has been C.cant has gone D.cant has been答案：C C may 四、 have to表示客观需要，意为“必须，不得不”，强调客观上的必要性。例 You have to be back before 10 oclock because the train leaves at 10:05.五、 shall1. 征求对方意见。用于主语是第一人称或第三人称的疑问句中。例 Henry is waiting outsid
7、e. Shall he come in, sir?2. 表示说话者给出的命令、警告、许诺或威胁等。用于主语是第二人称或第三人称的陈述句中。例 You shall be punished for what you have done. Tell Jerry he shall get a gift if he is nice.3. 在条约、规定、法令等文件中表示规定或义务等。例 Those belonging to our club shall wear uniforms.六、 should1. 表示劝告、建议、命令或义务。例 You should learn to respect your el
8、ders. You should help him because he is in trouble.2. 表示惊讶、忧虑、惋惜等情绪，意为“竟会，竟然”。例 Its a pity that you should be so careless. Why should anyone want to marry Tony?七、 ought to1. 意为“理应，应该”，表示一种义务或从道理或道义上来讲的一种责任，可用should替换。例 You ought to study hard.2. 意为“应该，应是”，表示一种推测，可用should替换。例 He is honest, so what he
9、 said ought to be true.八、 will/would1. 表示意愿，自愿或主动提出做什么。例 I will help you if you meet with trouble. 2.表示请求，would 比will 语气委婉。例 Would you please let me have a look?3.表示习惯或倾向。will 用于表示一般的习惯，would用于描述过去的习惯或例行的活动。例 Jealousy will spoil friendship. He would come to help us when he was free.4. will 表示规律性的“注定
10、会”。例 You will fail if you dont work hard. Man will die without air.九、 need1. 表示必要性，常用于疑问句和否定句中，neednt表示“不必”；对need引出的一般疑问句作肯定回答时用must而不用need，作否定回答是用neednt。例 This is a free service; you neednt pay for it. Need I hand in the application now? Yes, you must. / No, you neednt.十、 dare意为“敢，胆敢”，作情态动词时后跟动词原形，
11、主要用于疑问句、否定句和条件句中。例 How dare she do things like that to me? Dare you catch the mouse? No, I dare not.练习1. I have prepared all kinds of food for the picnic. Do you mean we_bring anything with us? A. cant B. mustnt C. shant D. neednt2. Days later, my brother called to say he was all right, but_say wher
12、e he was. A mustnt B shouldnt C wouldnt D mightnt3. It was sad to me that they, so poor themselves, _bring me food. A might B would C should D could 4. You_buy a gift, but you can if you want. A must B mustnt C have to D dont have to5. The new law states that people_drive after drinking alcohol. A w
13、ouldnt B neednt C wont D mustnt6. You neednt take an umbrella. It isnt going to rain. Well, I dont know. It _do. A might B need C would D should7. _I take the book out? Im afraid not. A. Will B. May C. Must D. Need 8. He_sleep, although he tried to, when he got on such a hunt for an idea until he ha
14、d caught it. A wouldnt B shouldnt C couldnt D mustnt9. What do you want to eat for lunch? 1 will prepare earlier today, Honey, you_. Lets go out to have something different. A. mustnt B. cant C. shouldnt D. dont have to10. -Is that our new English teacher? -Well, it _ be, but I am not quite sure. A
15、should B might C must D cant11. -What are you going to order?-Well, I think I _ try the fried eggs, but I am not sure yet.A must B might C cant D shouldnt答案：1.D 2.C 3.C 4.D 5.D 6.A 7.B 8.A 9.D 10.B 11.B 1( ) 1 John_ come to see us tonight, but he isnt very sure yet.A. may B. can C. has to D. must( )
16、 2 They _ do well in the exam.A. can be able to B. be able toC. can able to D. are able to( ) 3 -May I take this book out? -No, you_.A. cant B. may not C. neednt D. arent( ) 4 You_ go and see a doctor at once because youre got a fever.A. can B. must C. dare D. would( ) 5 -Can you speak Japanese?-No,
17、 I_.A. mustnt B. cant C. neednt D. may not2( ) 1 -He_ be in the classroom, I think. -No, he _ be in the classroom. I saw him go home a minute ago.A. can; may not B. must; may notC. may; cant D. may; mustnt( ) 2 -Shall I get one more cake for you, Dad? -Thanks, but you_, Ive had enough.A. may not B.
18、must not C. cant D. neednt( ) 3 Even the top students in our class cant work out this problem, so it be very difficult.A. may B. must C. can D. need( ) 4 He isnt at school. I think he _ be ill. A. can B. shall C. must D. has to( ) 5 _ I take this one?A. May B. Will C. Are D. Do3( ) 1 The children_ p
19、lay football on the road.A. cant B. can C. mustnt D. must( ) 2 You _ be late for school again next time.A. mustnt B. neednt C. dont have to D. dont need to( ) 3 -Must I do my homework at once?-No, you_.A. neednt B. mustnt C. cant D. may not4( ) 1 His arm is all right. He_ go and see the doctor.A. ha
20、s not to B. dont have toC. havent to D. doesnt have to( ) 2 He had to give up the plan, _ he?A. did B. didnt C. does D. doesnt( ) 3 They had to walk here, _ they?A. mustnt B. did C. didnt D. hadnt5( ) 1 He had better stay here, _ he?A. didnt B. dont C. hadnt D. isnt( ) 2 Youd better_late next time.A
21、. not to be B. not be C. wont be D. dont be( ) 3 Youd better _ your hair _ once a month.A. had; cut B. had; cuttedC. have; cut D. have; cutted( ) 4 You_ ask that man over there. Maybe he knows the way.A. had better not to B. had not better C. had better D. had better not6( ) 1 -Shall we go and visit
22、 the History Museum next Sunday?A. Here you are B. Sorry, I cant C. Yes, please D. Let me try( ) 2 -Why dont you ask Mike to go with us?-Thanks, _.A. I will B. I wont C. lean D. I may( ) 3 -_ I take the newspaper away?-No, you mustnt. You_read it only here.A. Must; can B. May; can C. Need; must D. M
23、ust; must7( ) 1 Excuse me. _ you please pass me that cup?A. Do B. Should C. Would D. Must( ) 2 _ you like to have another try?A. Could B. Will C. Would D. Do ( ) 3 -Would you like to go boating with us?-Yes, _.A. Id like B. I want C. Id like to D. I do 8( ) 1 You_ worry about your son. He will get w
24、ell soon.A. neednt B. cant C. mustnt D. have to( ) 2 The poor man needs our help, _ he?A. need B. neednt C. does D. doesnt( ) 3 -Must we do our homework first?-No, you_. You may have a rest first.A. mustnt B. neednt C. may not D. cant习题答案：1. 1-5 A D A B B2. 1-5 C D B C A3. 1-3 C A A4. 1-3 D B C5. 1-4 C B C C6. 1-3 B A B7. 1-3 C C C8. 1-3 A D B