概 说 助动词(auxiliary)主要有两类：基本助动词(primary auxiliary)和情态助动词(modal auxiliary)。 基本助动词有三个： have 和 be； do, 情态助动词有十三个： may, might; can, could; will, would; shall, should; must, need,
dare, used to, ought to. 上述两类助动词的共同特征是， 在协助主动词 构成限定动词词组时，具有作用词的功能： 1） 构成否定式： He didn’t go and neither did she. The meeting might not start until 5 o?clock. 2） 构成疑问式或附加疑问式： Must you leave right now? You have been learning French for 5 years, haven’t you? 3） 构成修辞倒装： Nowhere can he obtain any information about his sister. Hardly had he arrived when she started complaining. 4） 代替限定动词词组： A: Who can solve this crossword puzzle? B: Tom can. A: Shall I write to him? B: Yes, do. 情态助动词的特征 基本助动词与情态助动词最主要的区别之一是， 基本助动词本身没有词义， 而情态助动词则 有自己的词义，能表示说话人对有关动作或状态的看法，或表示主观设想： What have you been doing since? （构成完成进行体，本身无词义） I am afraid I must be going. （一定要） You may have read some account of the matter. （或许已经） 除此之外，情态助动词还有如下词法和句法特征： 1） 除 ought 和 used 以外，其他情态动词后面只能接不带 to 的不定式。如果我们把 ought to 和 used to 看做是固定词组的话，那么，所有情态动词无一例外地只能接不带 to 的不定 式： We used to grow beautiful roses. I asked if he would come and repair my television set. 2） 情态助动词在限定动词词组总总是位居第一： They need not have been punished so severely. 3） 情态助动词用于第三人称单数现在时的时候，没有词形变化，即其词尾无-s 形式： She dare not say what she thinks. 4） 情态动词没有非限定形式，即没有不定式、-ing 分词和-ed 分词形式： Still, she needn’t have run away. 5） 情态助动词的“时”的形式并不是时间区别的主要标志。在不少场合，情态助动词的现 在时和过去时形式都可以表示现在、过去或将来时间： Would you mind very much if I ask you to do something?
She told him he ought not to have done it. 6） 情态助动词之间是相互排斥的，即在一个限定动词词组中只能出现一个情态助动词，但 有时却可以与 have 和 be 基本助动词连用： You should have washed the wound. Well, you shouldn’t be reading a novel. 现将情态助动词的各种形式列表如下： 肯定式 may might can could will, ?ll would, ?d shall should must need dare used to ought to 否定式 may not might not can not, cannot could not will not, ?ll not would not, ?d not shall not should not must not need not dare not used not to ought not to 简略否定式 mayn?t mightn?t can?t couldn?t won?t wouldn?t shan?t shouldn?t mustn?t needn?t daren?t didn?t use(d) to usedn?t to oughtn?t to
情态助动词的意义和用法 情态助动词从最普通的意义上来说， 是修饰分句意义的一种方式， 它可以反映说话者对其表 述是否真实和可能的程度作出判断。但不同的情态助动词本身所包含的意义和用法又不同， 下面逐个分析。 1） can 和 could 的用法 1． 表示能力或客观可能性，还可以表示请求和允许。如： Can you finish this work tonight? Man cannot live without air. — Can I go now? — Yes, you can. 注意：①could 也可表示请求，预期委婉，主要用于疑问句，不可用于肯定句，答语应 用 can（即 could 不能用于现在时态的简略答语中） 。如： Could I come to see you tomorrow? Yes, you can. （否定答语可用 No, I?m afraid not.） ②can 表示能力时，还可用 be able to 代替。如： I?ll not be able to come this afternoon. 2． 表示惊异、怀疑、不相信的态度。 （主要用在否定句、疑问句或惊叹句中） Can this be true? How can you be so careless! This cannot be done by him. 3． “can(could) + have + 过去分词”的疑问或否定形式表示对过去发生的行为怀疑或
不肯定。如： He cannot have been to that town. Can he have got the book? 2） may 和 might 的用法 1． 表示许可。 表示请求、允许时，might 比 many 的语气更委婉一些，否定回答时要用 mustn?t 表 示“不可以”“禁止”“阻止”之意。如： 、 、 You may drive the car. — Might I use your pen? — No, you mustn’t. 用 May I ... 征询对方许可在文体上比较正式，在口气上比较客气。在日常口语中， 用 Can I ... 征询对方意见在现代口语中更为常见。 2． 用于祈使句中表示祝愿。如： May you succeed! 3． 表示推测、可能（疑问句不能用于此意） 。 He may be very busy now. 4． “may(might) + have + 过去分词”表示对过去发生的行为的推测。如： He may not have finished the work. 3） must 和 have to 的用法 1． 表示必须、必要。如： You must come in time. 回答 must 引出的问句时，如果是否定的回答，不能用 mustn?t，而要用 needn?t 或 don?t have to。 — Must we hand in our exercise books today? — Yes, you must. (No, you don?t have to.) 2． “must be + 表语”的结构表示推测，它的否定或疑问式用 can 代替 must。 This must be your pen. 3． “must + have + 过去分词” 的结构常用在肯定句中， 表示对过去发生的行为的推测。 它的否定或疑问式用 can 代替 must。 He must have been to Shanghai. 4． have to 的含义与 must 相似， 两者往往可以互换使用， have to 有各种形式， have 但 随 的变化而定。must 与 have to 有下列几点不同： ① must 表示的是说话人的主观看法，而 have to 则往往强调客观需要。如： The play is not interesting. I really must go now. I had to work when I was your age. ② must 一般只表现在，have 则有更多的时态形式。 ③ 二者的否定意义不大相同。如： You mustn’t go. 你可不要去。 You don’t have to go. 你不必去。 ④ 询问对方的意愿时应用 must。如： Must I clean all the room?
4） dare 和 need 的用法 1． need 表示“需要”或“必须” ，作情态动词时，仅用于否定句或疑问句中，在肯定 句中一般用 must, have to, ought to,或 should 代替。如： You needn’t come so early. — Need I finish the work today? — Yes, you must. 注意：needn?t + 不定式的完成式“表示本来不必做某事而实际上做了某事” 。如： You needn’t have waited for me. 2． Dare 作情态动词时， 主要用于疑问句、 否定句和条件从句中， 一般不用在肯定句中。 如： How dare you say I?m unfair. He daren’t speak English before such a crowd, dare he? 3． Dare 和 need 常用作实义动词，有时态、人称和数的变化，所不同的是，作实义动 词时，在肯定句中，dare 后面通常接带 to 的不定式，在否定和疑问句中，dare 后面 可接带 to 或不带 to 的不定式。如： I dare to swim across this river. He does not dare (to) answer. Don?t you dare (to) touch it! I wondered he dare (to) say that. He needs to finish it this evening. 5） shall 和 should 的用法 1． Shall 用于第一人称，表示征求对方的意愿。如： What shall we do this evening? 2． Shall 用于第一、 第三人称疑问句中， 表示说话人征求对方的意见或向对方请示。 如： Shall we begin our lesson? When shall he be able to leave the hospital? 3． Shall 用于第二、第三人称，表示说话人给对方命令、警告、允诺或威胁。如： You shall fail if you don?t work harder. （警告） He shall have the book when I finish reading. （允诺） He shall be punished. （威胁） 4． Should 表示劝告、建议、命令，其同义词是 ought to；在疑问句中，通常用 should 代替 ought to。如： You should go to class right away. Should I open the window? Should 的含义较多，用法较活，现介绍三种其特殊用法。请看下面的句子： ① I should think it would be better to try it again. 我倒是认为最好再试一试。 ② You are mistaken, I should say. 依我看，你是搞错了。 ③ I should advise you not to do that. 我倒是劝你别这样做。 ④ This is something I should have liked to ask you. 这是我本来想问你的。 从以上例句可以看出：情态动词 should 用于第一人称时可以表示说话人的一种谦 逊、客气、委婉的语气。 Should 还可以用在 if 引导的条件从句，表示一件事听起来可能性很小，但也不是完
全没有可能。相当于“万一”的意思。从句谓语由 should 加动词原形构成，主句谓 语却不一定用虚拟语气。如： ⑤ Ask her to ring me up if you should see her. 你万一见到她， 请让她给我打个电话。 ⑥ If you should change your mind, please let us know. 万一你改变主意，请通知我 们。 ⑦ Should I (If I should) be free tomorrow I will come. 万一我明天有时间，我就来。 此外，Why(or How) + should 结构表示说话人对某事不能理解，感到意外、惊异等 意思。意为“竟会” 。如： ⑧ Why should you be so late today? 你几天怎么来得这么晚？ ⑨ — Where is Betty living? — 贝蒂住在哪里？ — How should I know? — 我怎么会知道呢？ ⑩ I don?t know why you should think that I did it. 我真不知道你凭什么认为这件事 是我干的。 5． “should + have + 过去分词” 结构一般表示义务， 表示应该做到而实际上没有做到， 并包含一种埋怨、责备的口气。如： She should have finished it. I should have helped her, but I never could. You should have started earlier. 6） will 和 would 的用法 1． 表示请求、建议等，would 比 will 委婉客气。如： Would you pass me the book? 2． 表示意志、愿望和决心。如： I will never do that again. They asked if we would do that again. 3． 用“will be”和“will(would) + have + 过去分词”的结构表示推测，主要用于第二、 三人称。前者表示对目前情况的推测，后者表示对已经完成的动作或事态的推测。 如： This will be the book you want. He will have arrived by now. The guests would have arrived by that time. I thought you would have finished this by now. 4． Would 可表示过去反复发生的动作或某中倾向。 Would 表过去习惯时比 used to 正式， 并没有“现已无此习惯”的含义。如： The wound would not heal. During the vacation he would visit me every week. 5． 表料想或猜想。如： It would be about ten when he left home. What would she be doing there? I thought he would have told you all about it. 7） ought to 的用法 1． Ought to 表示应该。如：
You ought to take care of him. 2． 表示推测。注意与 must 表示推测时的区别： He must be at home by now. （断定他已到家） He ought to be home by now. （不十分肯定） This is where the oil must be. （比较直率） This is where the oil ought to be. （比较含蓄） 3． “ought to + have + 过去分词”表示过去应做某事而实际未做。如： You ought to have asked him (but you didn?t). 这时，ought to 和 should 可以互相换用。 注意：在美国英语中，ought to 用于否定句和疑问句时，to 可以省略。如： Ought you smoke so much? You oughtn’t smoke so much. 8） used to，had better，would rather 的用法 1． Used to 表示过去的习惯动作或状态， 现在已不存在， 在间接引语中， 其形式可不变。 如： He told us he used to play football when he was young. 在疑问句、否定句、否定疑问句或强调句中，可有两种形式： 疑问句 否定句 Did you use to go to the same school as your brother? Used you to go to the same school as your brother? I usedn’t to go there. I didn’t use to go there. Usen’t you to be interested in the theatre? Didn’t you use to be interested in the theatre? I certainly used to smoke, but it was a long time ago. I certainly did use to smoke, but it was a long time ago.
Usedn?t 亦可拼作 usen?t，但发音皆为[ju:znt]。 否定疑问句
其反意疑问句或简略回答中，也有两种形式： She used to be very fat, didn’t she? （正式）/ use(d)n’t she? （口语） Did you use to play chess? Yes, I did. Used you to get up early in the morning? Yes, I did. (Yes, I used to.) 2． Had better 意为“最好” ，后接不带 to 的不定式。如： — We had better go now. — Yes, we had (we?d better / we had better). Hadn’t we better stop now? (Had we better not stop now?) I think I’d better be going. （用于进行时态，表“最好立即” ） You had better have done that. （用于完成时态，表未完成动作） 注：①had best 与 had better 同意，但较少用。②You had better … 用于同辈或小辈， 对长辈不可用。 3． Would rather 意为“宁愿” ，表选择，后接不带 to 的不定式。如： I’d rather not say anything. Would you rather work on a farm?
— Wouldn’t you rather stay here? — No, I would not. I?d rather go there. 由于 would rather 表选择，因而后可接 than。如： I would rather work on a farm than in a factory. I would rather watch TV than go to see the film. I would rather lose a dozen cherry trees than that you should tell me one lie. I’d rather you didn’t talk about this to anyone. （句中的?d rather 不是情态动词， would 在此是表愿望的实义动词） 练习部分 一、基础训练 1）单项选择 1. You ___ hand it in at once, you may hand it in tomorrow. (A) needn't (B) may not (C) can't (D) must not 2. "That must be a mistake." "No it ___ a mistake." (A) must not be (B) needn't be (C) cannot be (D) would not be 3. You ___ go now. It's getting late. (A) had rather (B) would (C) had better (D) would 4. Since the bus is crowded, we ___. (A) had better walk to home (B) have better walk home (C) had better walk home (D) had better to walk home 5. "You ___ come in now, Mary! It's getting cold!" “I ___ go on playing in the garden." (A) had better...had better (B) would rather...had better (C) had better...would rather (D) had better...would have better 6. When I was a boy, I ___ chocolate. (A) would like (B) was used to like (C) should like (D) used to like 7. I wasn't supposed to go to the movies, but I ___ myself. (A) cannot help (B) couldn't but (C) had to help (D) couldn't help 8. Looking at my determined face, the big boy ___ pick up the fight. (A) dares not (B) dare not (C) doesn't dare (D) dares not to 9. He began to write two hours ago. He ___ have finished the article now. (A) must (B) ought (C) ought to (D) had to 10. You ___ to the meeting this afternoon if you have something important to do. (A) needn't to come (B) don't need come (C) don't need coming (D)needn't come 11. ___ you be here at eight o'clock tomorrow morning? (A) Would (B) Should (C) Can (D) Could 12. ___ I have a talk with the Party Secretary now? (A) Will (B) Did (C) May (D) Can 13. "You ___ read that article if you don?t want to.” (A) needn't (B) mustn?t (C) haven't (D) can?t 14. When the storm comes all windows ___. (A) ought to close (B) ought to be closing (C) ought to be closed (D) ought to closed 15. I ___ me what happened.
(A) would like you tell (B) would like you to tell (C) would like you telling (D) would like you that you tell 16. I hope you can visit my country soon, because___ to show you some of the beautiful places near my home. (A) I like (B) I'd like (C) I will like (D) I shall like 17. She ___ for yesterday's test, but she didn?t. (A)should have studied (B) would study (C) might be studying (D)must have studied 18. He ___ breakfast at eight o'clock when he lived alone. But nowadays he ___ it at seven. (A) was used to have ... is having (B) was used to having ...is having (C) used to have ... has (D) used to having ...was 19. In the old society Grandpa Zhou ___ to work long hours a day. (A) was working (B) was having (C) had (D) has 20. Everybody ___ in bed. (A) has to spend some time (B) have to spend some time (C) has to spend sometimes (D) have to spend sometimes 2) 选择合适的词或词组填空 1. I have a headache. I __________ take an aspirin. (had better; would better) 2. He looks sleepy. He must __________ bed very late last night. (go; have gone) 3. I want to go to the office, but you __________ with me. (need not to go; need not go) 4. I ought __________ those books to the library last week. (to have taken; to take) 5. The mother is telling her son, “You __________ eat with your fingers!” (wouldn?t; mustn?t) 6. He was a good swimmer so he _______ swim to the river bank when the boat sank. (was able to; could) 7. To travel from England to Scotland you __________ a passport. (don?t need; needn?t) 8. He went on foot, but he __________ by bus. (ought have gone; should have gone) 9. A: Did Ken take the job in the bookstore? B: No, but I think he __________. (must have; should have) 10. He __________ talk for hours, if you let him. (can; will) 11. You __________ use this toothbrush, it?s mine. (may not; shall not) 12. No matter what people say, I __________ do as I like. (shall; will) 13. “I?m willing to let you take whatever you like.” Means “you ______ take whatever you like.”
(shall; will) 14. A: I haven?t felt well for a week. B: You __________ see a doctor. (had better; should have to) 15. A: He is late, __________ he have missed the bus? B: Yes, he must have missed the bus. (Can; Must) 二、强化练习 1) 选择填空 1. I didn?t see her in the meeting room this morning. She _____ at the meeting. A. mustn?t have spoken B. shouldn?t have spoken C. needn?t have spoken D. couldn?t have spoken 2. One ought _____ for what one hasn?t done. A. not to be punished B. to not be punished C. to not punished D. not be punished 3. If you really want yourself to be in good health, you must ___ always ___ so much. A. not; be smoking B. not; have smoked C. not; to smoke D. be not; smoking 4. With so much work on hand, you _____ to see the game last night. A. mustn?t go B. shouldn?t go C. couldn?t have gone D. shouldn?t have gone 5. Most of the students felt rather disappointed at the English party. They say that it ______ better organized. A. had been B. had to be C. must have been D. could have been 6. I?m surprised that he _____ in the exam. A. should fail B. would have failed C. may have failed D. should have failed 7. The little girl _____ there alone. A. not dare go B. dares not go C. dare not go D. dare not to go 8. “Must we do it now?” “No, you _____.” A. won?t B. needn?t C. can?t D. don?t 9. He said he would rather not _____ it right now. A. doing B. to do C. do D. to be doing 10. You _____ to the meeting this afternoon if you have something important to do. A. needn?t to come B. don?t need come C. don?t need coming D. needn?t come 11. Put on more clothes. You _____ be feeling cold with only a shirt on. A. can B. could C. would D. must 12. I _____ play football than baseball. A. would rather B. had better C. like better D. prefer 13. I thought you _____ like something to read, so I have brought you some books. A. may B. might C. could D. must 14. There was plenty of times. She _____. A. mustn?t have hurried B. couldn?t have hurried C. must not hurry D. needn?t have hurried
15. The plant is dead. I _____ it more water. A. will give B. would have given C. must give D. should have given 16. You _____ return the book now. You can keep it till next week if you like. A. can?t B. mustn?t C. needn?t D. may not 17. It?s still early, you _____. A. mustn?t hurry B. wouldn?t hurry C. may not hurry D. don?t have to hurry 18. Please open the window, _____? A. can?t you B. aren?t you C. do you D. will you 19. We _____ for her because she never came. A. mustn?t have waited B. shouldn?t have waited C. mustn?t wait D. needn?t wait 20. — May I stop here? — No, you _____. A. mustn?t B. might not C. needn?t D. won?t 21. It?s a fine day. Let?s go fishing, _____. A. won?t we B. will we C. don?t we D. shall we 22. I didn?t see her in the meeting room this morning. She _____ at the meeting. A. mustn?t have spoken B. shouldn?t have spoken C. needn?t have spoken D. couldn?t have spoken 23. — Please don?t make a noise. — _____. I?ll be as quiet as a mouse. A. Yes, I won?t B. No, I won?t C. No, I will D. Yes, I will 24. The young man has made so much noise that he _____ not have been allowed to attend the concert. A. could B. must C. would D. should 25. — Where is John? — He _____ in the library. A. should be B. must be C. can be D. must have been 26. Since the road is wet this morning, _____ last night. A. it must rain B. it must be raining C. it must have rained D. it must have been rain 27. — Will your brother stay home tonight? — I?m not quite sure. He _____ to the cinema tonight. A. must go B. can go C. may go D. may be going 28. She?s already two hours late. What ______ to her? A. can have happened B. may have happened C. should have happened D. must happen 29. You must be a writer, _____? A. mustn?t you B. are you C. must you D. aren?t you 30. I got up early that morning, but I _____ so because I had no work to do. A. mustn?t have done B. didn?t need to do C. needn?t have done D. can?t have done 31. He _____ have come here yesterday, but he didn?t. A. could B. should C. ought to D. all the above 32. I missed the last bus, so I _____ go home on foot.
A. must B. have to C. may D. had to 33. He ought to win the first prize, _____ he? A. oughtn?t B. shouldn?t C. mustn?t D. both A and B 34. Everyone _____ do his best for the modernizations of our country. A. can B. may C. should D. might 35. Let?s clean our classroom, _____? A. will you B. don?t we C. shall we D. do you 36. Let us play basketball, ______? A. will you B. don?t we C. shall we D. do you 37. He asked me for this book many times. Please tell him that he _____ have it tomorrow. A. must B. may C. shall D. both B and C 38. “Your phone number again? I _____ quite catch it.” “It?s 9568442.” A. didn?t B. couldn?t C. don?t D. can?t 39. Mother _____ us stories when we were children. A. was used to tell B. is used to telling C. used to tell D. used to telling 40. She would rather _____ more money on books _____ on clothes. A. cost … not B. to spare … don?t C. pay … than D. spend … than 2）强化练习题 1) You____ all those clothes! We have a washing machine to do that sort of thing. A) needn't have washed B) shouldn't have washed C) must not have washed D) can not have washed 2) John's score on the test is the highest in the class; he____ last night. A) should study B) should have studied C) must have studied D) must have to study 3) The room is in a terrible mess; it ____cleaned. A) can't have been B) shouldn't have been C) mustn't have been D) wouldn't have been 4) Nobody knows how people first came to these islands. They ____ from South America on rafts. A) must have sailed B) can sail C) might have sailed D) should have sailed 5) Mary was not in her bedroom yesterday afternoon. She ____ in her classroom. A) should have been B) must have been C) must be D) should be 6) Bob said he was going to join our club but he didn't. He ____ his mind. A) can't have changed B) wouldn't have changed C) must have changed D) shouldn't have changed 7) You____ to town to see the film yesterday. It will be on TV tonight. A) needn't go B) had better not go C) should not go D) needn't have gone 8) We____ the letter yesterday, but it didn't arrive. A) must receive B) ought to receive C) must have received D) ought to have received 9) With all the work on hand, he____ to the cinema last night. A) mustn't go B) shouldn't have gone C) could not go D) couldn't have gone 10) Eve was late for class again. She ____earlier.
A) should get up B) must get up C) need to get up D) should have got up 11) I am feeling sick. I____ so much chocolate. A) needn't have eaten B) couldn't have eaten C) mustn't have eaten D) shouldn't have eaten 12) I didn't send out my application form last week, but I ____. A) had B) would do C) should have D) might have to 13) Walking alone in the deserted village, John was scared. He thought he____ Tom to go with him. A) might have asked B) should asked C) must have asked D) should have asked 14) When I got to the cinema, the film had already started; I____ there earlier. A) ought to get B) ought to have got C) must have got D) must get 15) The road was muddy. It____ last night. A) must rained B) must have rained C) must be rained D) could have rained 16) She can speak quite fluent English. She____. A) must been in the U.S.A. for some time B) must have been in the U.S.A. for some time C) should have been in the U.S.A. for some time D) May be in the U.S.A. for some time 17) You should bear in mind that he is not so strong as he____. A) was used to be B) used to be C) was used to D) use to 18)“We didn't see him at the exhibition yesterday.” “He ___it.” A) mustn't visit B) can't have visited C) should have gone to see D) may see 19) Mary ____my letter, otherwise she would have replied before now. A) should have received B) has received C) couldn't have received D) ought to have received 20) I ____ you a valuable present for your birthday, but I was short of money. A) would have liked to give B) liked to give C) have liked to give D) would like to give 21)“Where ____ my umbrella?” “Somebody ____ it away by mistake.” A) is, must have taken B) is, must take C) have been, must take D) is, takes 22) What ____ would happen if the director knew you felt that way? A) will you suppose B) you suppose C) do you suppose D) you would suppose 23) Two eyes ____see more than one. A) can B) may C) will D) should 24) ____ you continue in your efforts and achieve new and greater successes. A) Would B) Will C) May D) Should 25) We ought to help each other in our work, ____? A) oughtn't we B) should we C) shouldn't we D) ought to we 26) Tom ____ better than to ask Dick for help. A) shall know B) shouldn't know C) has known D) should have known 27) You ____ your tooth pulled out before it rot completely.
A) had better got B) had to get better C) had better to get D) had better get 28) When we got to the cinema, the film hasn't started yet, so we ____. A) needn't hurry B) didn't need hurry C) needn't to hurry D) needn't have hurried 29) It was really very dangerous; you ____ him seriously. A) might have injured B) could injure C) should have injured D) must injure 30) As he had heart attack, he was told that he ____ continue the work. A) needn't B) may not C) mustn't D) can't 31) An Englishman who ____not speak Italian was once traveling in Italy. A) must B) could C) may D) might 32) I ____like to make a suggestion. A) could B) would C) must D) might 33) I know things are hard with you, but you ____try to get over the difficulties. A) can B) may C) must D) ought 34 I can't find the recorder in the room. It ____ by somebody. A) may have been taken away B) may leave C) may take away D) must have taken away 35) He ____the 9:20 train because he didn't leave home till 9:25. A) can reach B) could catch C) may not catch D) couldn't have caught 3) 单句改错（先判断句子是否正确，正确的句子不需改动。 ） 1. Ought you smoke so much? 2. If Fred didn?t leave here before five, he mustn?t be home yet. 3. I?m going home. I don?t want to but I must, because my mother asked me not to go out after dark. 4. After I?ve finished my course, I?ll can speak English fluently. 5. I can be seeing the top of the tower in this bedroom. 6. You are not able to play football in the park on Sundays, though you may do so on weekdays. 7. He can?t be working at this hour! 8. Mary Blake ought to not be home by now. 9. His luggage is still here, he must not have left. 10. I used to writing poetry myself when I was his age.
三、能力提升 1. You _____ return the book now. You can keep it till next week if you like. A. can?t B. mustn?t C. needn?t D. may not 2. Where is my pen? I _____ it. A. might lose B. would have lost C. should have lost D. must have lost 3. I wish I _____ you yesterday. A. seen B. did see C. had seen D. were to see 4. I didn?t hear the phone. I _____ asleep. A. must be B. must have been C. should be D. should have been 5. If my lawyer _____ here last Saturday, he _____ me from going. A. had been; would have prevented B. had been; would prevent C. were; would prevent D. were; would have prevented 6. He _____ you more help, even though he was very busy. A. might have given B. might have C. may have given D. may give 7. If it _____ for the snow, we _____ the mountain yesterday. A. were not; could have climbed B. were not; could climb C. had not been; could have climbed D. had not been; could climb 8. Without electricity human life _____ quite difficult today. A. is B. will be C. would have been D. would be 9. A computer _____ think for itself, it must be told what to do. A. can?t B. couldn?t C. may not D. might not 10. Jenny _____ have kept her word. I wonder why she changed her mind. A. must B. should C. need D. would 11. We _____ last night, but we went to the concert instead. A. must have studied B. might study C. should have studied D. would study 12. — Could I borrow your dictionary? — Yes, of course you _____. A. might B. will C. can D. should 13. Tom ought not to _____ me your secret, but he meant no harm. A. have told B. tell C. be telling D. having told 14. — If he _____, he _____ that food. — Luckily he was sent to the hospital immediately. A. was warned; would not take B. had been warned; would not have taken C. would be warned; had not taken D. would have been warned; had not taken 15. Peter _____ come with us tonight, but he isn?t very sure yet. A. must B. may C. can D. will 16. I told Sally how to get here, but perhaps I _____ for her. A. had to write it out B. must have written it out C. should have written it out D. ought to write it out 17. I didn?t see your sister at the meeting. If she _____, she would have met my brother. A. has come B. did come C. came D. had come 18. — Shall I tell John about it?
— No, you _____. I?ve told him already. A. needn?t B. wouldn?t C. mustn?t D. shouldn?t 19. 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 20. It?s nearly seven o?clock. Jack _____ be here at any moment. A. must B. need C. should D. can 21.— There were already five 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 22. Johnny, you _____ play with the knife, you _____ hurt yourself. A. won?t; can?t B. mustn?t; may C. shouldn?t; must D. can?t; shouldn?t 23. The fire spread through the hotel very quickly but everyone _____ get out. A. had to B. would C. could D. was able to 24. — When can I come for the photos? I need them tomorrow afternoon. — They _____ be ready by 12:00. A. can B. should C. might D. need 25. — I stayed at a hotel while in New York. — Oh, did you? You _____ with Barbara. A. could have stayed B. could stay C. would stay D. must have stayed 26. — Will you stay for lunch? — Sorry, _____. My brother is coming to see me. A. I mustn?t B. I can?t C. I needn?t D. I won?t 27. — Are you coming to Jeff?s party? — I?m not sure. I _____ go to the concert instead. A. must B. would C. should D. might 28. — Write to me when you get home. — _____. A. I must B. I should C. I will D. I can 29. I was really anxious about you, you _____ home without a word. A. mustn?t leave B. shouldn?t have left C. couldn?t have left D. needn?t leave 30. — Is John coming by train? — He should, but he _____ not. He likes driving his car. A. must B. can C. need D. may 解答部分 基础训练部分 1——5 ACCCC 6——10 DDBCD 11——15 CCACB 16——20 BACCA 1. had better 2. have gone 3. need not go 4. to have taken 5. mustn?t 6. was able to 7. don?t need 8. should have gone 9. should have 10. will 11. shall not 12. will 13. shall 14. had better 15. Can 强化练习 1）选择填空部分答案解析
1. D. must 表示推测时不用于否定句；shouldn?t have done sth. 表示“本不应该做某事而实 际上做了” ；needn?t have done sth. 表示“本来不必做某事而实际上做了” ；couldn?t have done sth. 表示“不可能做过某事” 。根据题意，选 D。 2. A. 情态动词 ought 后要接带 to 的不定式，ought to do 的否定式是 ought not to do，所以 答案是 A。 3. A. must not always be doing sth. 表示“不要老是做谋事” ，含有埋怨、指责、反感等感情 色彩。 4. D. 题中的 A 项和 B 项都指现在情况； couldn?t have gone 表示 “不可能去过”shouldn?t have ； gone 表示“本不应该去而实际上去了” 。根据题意，选 D。 5. D. could have done sth. 表示“本来能够做某事而实际上未能做成” 。 6. D. should 可用于表示惊奇、 感叹、 不满等感情色彩的句子， 如指过去的动作， 则要用 should have done sth. Would 和 may 通常不带感情色彩。 7. C. 题中的 dare 是情态动词，后接不带 to 的不定式，主要用于疑问句、否定句和条件句 中。 8. B. must 开头的疑问句，否定答语用 needn?t 或 don?t have to。 9. C. would rather 通常也视为情态动词 （组）后接动词原形， ， 其否定形式为 would rather not。 10. D. need 作为情态动词，其否定形式为 needn?t；作实义动词时，其否定形式为 don?t (doesn?t) need to do。 11. D. must 用在肯定句中表推测时，语气比 could, would 等肯定得多。此处“must + 不定 式进行式”表“想必正在??”之意。 12. A. would rather … than …，意为“宁愿（做）??而不（做）??” 。 13. B. 由句意可知，这是对过去发生的事情不太有把握的推测。 14. D. needn?t have done 意为“过去不必做而做了某事” 。 15. D. should have done 表示“过去应该做而没有做某事” 。 16. C. can?t（不能） ，mustn?t（不准） ，may not（不可以） ，均不合题意。 17. D. don?t have to = needn?t 18. D. will 用在第二人称的疑问句中，为询问（或征求）对方的意愿或向对方提出请求之 意。 19. B. should not have done 表示“过去不应该做而做了某事” ，含有“后悔”“责备”“劝 、 、 告”“批评”之意。 ， 20. A. may 开头的疑问句，否定答语常用 mustn?t。 21. D. 疑问句中 shall 用于第一、三人称，用来征询对方的意见。 22. D. 推测“她不可能在会上发言” ，must 表示推测时，不能用于否定句中。 23. B. will 在此处表示“意志（向）。 ” 24. D. should not have done 表示“过去不应该做而做了某事” ，含有“后悔”“责备”“劝 、 、 告”“批评”之意。 ， 25. B. must do 表示对现在的事实进行推测。 26. C. must have done 用于对过去发生的事情进行推测，且较有把握。 27. C. 表示推测时，must 比 may 语气肯定。 28. A. can 表推测，只用于否定句和疑问句中。 29. D. must 表示推测时，其后的反意问句有两种情况：①对现存状态（现在的事实）进行 推测时，反意疑问句中动词用其一般现在形式。②对过去发生的事情进行推测时，若有表 过去的时间状语，反意问句用动词的过去式。
30. C. needn?t have done 表示“过去不必做而做了某事” ，若表示“不必做某事（且实际上 未做） ”则用“didn?t / don?t / doesn?t need to.” 31. D. A 表示“本能够” ，B, C 表“本应该” 。 32. D. have to 表示客观上要求做某事，must 表示主观上认为必须做某事。 33. D. ought to 的反意问句应用 oughtn?t 或 shouldn?t 开头。 34. C. should 含“按理应该做??”“有义务做??”之意。 、 35. C. Let?s 中的 us 一般包括对方在内。 36. A. Let us 中的 us 一般不包括对方在内。 37. D. may 和 shall 均可表“允诺” 。 38. A. 由句后得知句意为“我开始没听清楚对方的电话号码” ，为对过去的事实或发生动作 的表述。 39. C. used to do“过去（常）做某事” ，be used to doing“习惯于做某事” 。 40. D. would rather 后接动词原形。Spend … on sth.为常用结构。 强化练习 2）答案 1——5 ACACB 6——10 CDDDD 11——15 DCDBB 16——20 BBCCA 21——25 ACACA 26——30 DDDAC 31——35 BBCAD 强化练习 3）单句改错答案 1. (No mistake)在否定句和疑问句中，ought 后面的 to 可省。 2. mustn?t — can?t 3. must — have to 4. can — be able to 5. be seeing — see 6. are not able to — cannot 7. (No mistake) 8. to not — not to 9. must — can 10. writing — write 能力提升答案全解 1．C 从原题中 You can keep it till next week if you like 这一信息句可知， “你不必现在还” 。 2．D 从原题中 Where is my pen?这一信息句可告诉考生， “笔丢了” ，丢的动作是过去发生 的。因此用 must + have done 表示对过去事实的肯定猜测。 3．C 原题中的 yesterday 这一信息词告诉考生，在 wish 后的宾语从句中，用过去完成时， 表示与过去事实相反的愿望。 4．B 从原题中的 I didn?t hear the phone.这一信息可以判断出，用 must have done 表示过去 事实的准确的肯定猜测。 5．A 从原题中 last Saturday 这一信息词可知，条件句中用表示与过去 事实相反的过去完 成时，主句用 would + have done。 6．A might have + 过去分词，在次是虚拟语气，表示“本来可以给你更多的帮助” ，而事 实则是帮助较少。 7．C 从原题中的 yesterday 这一信息词暗示考生，该句应选用与过去事实相反的过去完成 时，If it had not been for … “要不是因为??” 。 8．D 原题中的 Without electricity 相当于一个条件句：If there were no electricity,故主句用 human life would be quite difficult today. 9．A can 可以表示一种客观上的能力，本句 can?t，表示“不能，不会” 。 10．B 从原题总的“I wonder why she changed her mind” “我不知道为何他改变了主意了。 ” 这句话告诉考生 Janny 没有守诺言。因此，用 should + have done，表示“过去本应该
做某事，而实际上没有做” 。 11．C 可参看 10 题。意思是： “昨晚本应该学习，但是却去听音乐会了。 ” 12．C 原题中的 could 不是过去时，而表示一种委婉、客气的礼貌用语。因此用 could 提 问时， can 回答。 用 同样用 would， might 提问， will 和 may 回答。 用 [注意]①— Would you rather do such a thing? — Yes, I would. ②— Would you like some tea? — Yes, I would. 这两个对话中的 would rather，would like 是惯用法，故不能用 will 来回答。因为在 这两个句型中，will 不能去替换 would。 13．A 可参看 10、15 题。该句意思是： “汤姆本来不该告诉我你的秘密，但他没有伤害你 的意思。 ”ought not to have done = shouldn?t have done 14．B 从答语中的 Luckily he was sent to the hospital immediately 这一信息句可提示考生， 条件句应填表示与过去事实相反的时态。 15．B 从原题中的 but he isn?t very sure yet 这一信息句可暗示考生，Peter 当晚来的可能性 不大。A 是“准来，肯定来” 是“将要来” ，D 。 16．C 可参看 10、11、13 题。 “本应该”而事实上没有?? 17．D 从原题中 I didn?t see your sister at the meeting 和后文 she would have met my brother 这两个信息句可知，if 条件句中应填与过去事实相反的过去完成时。可参看 6、7、 14 题。 18．A 你不必告诉他。因为 I?ve told him already 这一信息句已暗示考生了。 19．C 当 as if 引导虚拟语气的句子是，如果主句与从句中的谓语词所表达的动作同时发生 时，as if 后接一般过去时。例如：He walked as if he were lame.如果从句中的谓语动作 发生个在主句谓语动作之前，则用过去完成时。例如：He talked as if he had known the secret.不论主句中的谓语是现在时还是过去时。 20．C 只要考生抓住 nearly 一词和后文 at any moment（随时的意思）这两个信息词语，就 能很快选出 C 项，表示逻辑推测，意思是“快七点钟了，杰克一会儿就该到了。 ” 21．D 根据句意，是对过去情况的推测。 “当时决不可能是一次舒服的乘车。 ”must 表示对 过去的推测只能用于肯定句。 22．B mustn?t 表示“禁止” ；may 表示“有可能” 。句子的意思是： “你不可以玩刀，可能 会伤你自己。 ” 23．D 该题在考考生 could 与 was able to 之间的区别。Was able to 表示在困难的情况下， 经过一番周折而“能??” ，并且成功地做了。 24．B 该题考查情态动词 should 表推测的用法。Can 和 might 都可以表示可能性，用 might 则语气更加不肯定。Need 表示“需要”“必需” 、 。Should 可以表示推测，结合实际， 合乎逻辑， “应当” 意为 、 “该” 根据第一个说话者说的 I need them tomorrow afternoon 。 的语境，可以确定正确答案为 B。 25．A 该题在考查“情态动词+不定式的完成式”的用法，从会话的语境看，空白处应填 “could + have +过去分词”表示过去本来能做到的事而事实上没有做到。 26．B 该题考查表示请求的英语口语，用 will 来向第二人称提问的疑问结构，是表达一种 意愿和请求，是以疑问的形式来表达较为婉转的祈使语气，意思是“请你??，好 吗？” ，对于这种问句的肯定答语可用 Sure! Certainly! Yes, of course. I?d be glad to 等； 否定回答通常是 I?m sorry, I can?t. No, I?m afraid I can?t. I?m sorry, but … I ?d like to, but …等。 27．D might 表示“可能性” 。
28．C 意思是“我会的” 。对祈使句的肯定回答。 29．B shouldn?t have done 为本来不该做某事，而事实上做了。 30．D 用 may not 可表示“可能不” 。而 can not 则表示断然的否定推测“不可能” 。A，C 意思不符。