情态动词教师档.doc

情态动词用法归纳 情态动词有can (could), may (might), must, have to, shall (should, will (would), dare (dared), need (needed), ought to等。 情态动词无人称和数的变化；不能单独使用，必须与其后的动词原形构成谓语 1、 各情态动词的用法(一) can, could 1) 表示能力（体力、知识、技能）。 Can you lift this heavy box?（体力） Mary can speak three languages.（知识） Can you skate?（技能） 此时可用be able to代替。Can只有一般现在时和一般过去式；而be able to则有更多的时态。 Ill not be able to come this afternoon. 当表示“经过努力才得以做成功某事”时应用be able to，不能用Can。如： He was able to go to the party yesterday evening in spite of the heavy rain. 2) 表示请求和允许。 -Can I go now? - Yes, you can. / No, you cant. 此时可与may互换。在疑问句中还可用could, might代替，不是过去式，只是语气更委婉，不能用于肯定句和答语中。 - Could I come to see you tomorrow? - Yes, you can. ( No, Im afraid not. ) 3) 表示客观可能性（客观原因形成的能力）。 Theyve changed the timetable, so we can go by bus instead. This hall can hold 500 people at least. 4) 表示推测（惊讶、怀疑、不相信的态度），用于疑问句、否定句和感叹句中。 Can this be true? This cant be done by him. How can this be true? 例 - I think Miss Gao must be in the library. She said she would go there. - No. She _ be there, I have just been there.A.cant B.mustnt C.neednt D.wouldntcould的用法（1） can的过去式， 意为“ 能、 会” ， 表示过去的能力。 如：He could write poems when he was 10. 他十岁时就会写诗。（2）could 在疑问句中， 表示委婉的语气， 此时 could 没有过去式的意思。如:Could you do me a favor? 你能帮我个忙吗？-Could I use your pen? 我能用一下你的钢笔吗?-Yes, you can. 可以。(二)、 may, might 1) 表示请求和允许。might比 may语气更委婉，而不是过去式。否定回答时可用cant 或mustnt，表示“不可以，禁止”。 -Might/ May I smoke in this room? - No, you mustnt. - May/Might I take this book out of the room? - Yes, you can. (No, you cant / mustnt. ) 用May I.？征徇对方许可时比较正式和客气，而用Can I.？在口语中更常见。例-_ I borrow your MP3? -Sure . Here you are.A. May B.Should C.Must D. Would 2）用于祈使句，表示祝愿。 May you succeed! 3) 表示推测、可能性（不用于疑问句）。 might不是过去式，它所表示的可能性比may小。 1He may /might be very busy now. 2Your mother may /might not know the truth. (三)、 must, have to 1) 表示必须、必要。 You must come in time. 在回答引出的问句时，如果是否定的，不能用mustnt（禁止，不准），而用neednt, dont have to（不必）. - Must we hand in our exercise books today? - Yes, you must. - No, you dont have to / you neednt. 2) must是说话人的主观看法， 而have to则强调客观需要。Must只有一般现在时， have to 有更多的时态形式。 1 Playing with him isnt interesting, I really must go now. 2 I had to work when I was your age. 3) 表示推测、可能性（只用于肯定的陈述句） 1 Youre Toms good friend, so you must know what he likes best. 2 Your mother must be waiting for you now. must否定形式mustnt表示“ 一定不要 ” “千万别” “禁止, 不许”. 如：You mustnt play with fire. 你不许玩火。You mustnt be late. 你一定不要迟到。对must引导的疑问句，肯定回答为must， 否定回答为neednt 或 dont have to .如：-Must I finish my homework? 我现在必须完成作业吗？ -No, you neednt.不，你不必。当must表示 肯定的判断、推测时，其反意疑问句要用实际问句的助动词来构成。如： She must have finished writing, hasnt she?她一定已经写完了， 不是吗？(四)、 dare, need 1) dare作情态动词用时, 常用于疑问句、否定句和条件从句中, 过去式形式为dared。 1 How dare you say Im unfair? 2 He darent speak English before such a crowd, dare he? 3 If we dared not go there that day，we couldnt get the beautiful flowers.2) need 作情态动词用时, 常用于疑问句、否定句。在肯定句中一般用must, have to, ought to, should代替。 用need 提问时，肯定回答为 must，否定回答为 neednt 。 如：1You neednt come so early. 2. - Need I finish the work today? - Yes, you must. / No, you neednt. 3) dare和 need作实义动词用时， 有人称、时态和数的变化。在肯定句中，dare后面常接带to的不定式。在疑问句和否定句中，dare后面可接带to或不带to的不定式。而need后面只能接带to的不定式。 1. I dare to swim across this river. 2. He doesnt dare (to) answer. 3. He needs to finish his homework today. 练习1(A) 1 John_ come to see us tonight, but he isnt very sure yet. A. may B. can C. has to D. must(D) 2 They _ do well in the exam. A. can be able to B. be able to C. can able to D. are able to(A) 3 -May I take this book out? -No, you_. A. cant B. may not C. neednt D. arent(B) 4 You_ go and see a doctor at once because youre got a fever. A. can B. must C. dare D. would(B) 5 -Can you speak Japanese? -No, I_. A. mustnt B. cant C. neednt D. may not(五)、 shall, should 1) shall 用于第一三人称，征求对方的意见。 What shall we do this evening? 2) shall 用于第二、三人称，表示说话人给对方的命令、警告、允诺或威胁。 1. You shall fail if you dont work hard.(警告) 2. He shall have the book when I finish it.(允诺) 3. He shall be punished.(威胁) (六)、 will, would 1) 表示请求、建议等，would更委婉。 Will / Would you pass me the ball, please? 2) 表示意志、愿望和决心。 1. I will never do that again. 2. They asked him if he would go abroad. 3) would表示过去反复发生的动作或某种倾向。would表示过去习惯时比used to正式，且没有“现已无此习惯”的含义。 1. During the vacation, he would visit me every other day. 2. The wound would not heal. 4) 表示估计和猜想。 It would be about ten oclock when she left home. 2(C) 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 not C. may; cant D. may; mustnt(D) 2 -Shall I get one more cake for you, Dad? -Thanks, but you_, Ive had enough. A. may not B. must not C. cant D. neednt(B) 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(C) 4 He isnt at school. I think he _ be ill. A. can B. shall C. must D. has to(A) 5 _ I take this one? A. May B. Will C. Are D. Do (七)、 should, ought to, had better1) should, ought to表示“应该”，ought to表示义务或责任，比should语气重。 1. I should help her because she is in trouble. 2. You ought to take care of the baby. 2) 表示劝告、建议和命令。should, ought to可通用，但在疑问句中常用should。 1. You should / ought to go to class right away. 2. Should I open the window? 3) 表示推测 should , ought to (客观推测), must(主观推测)。 1.He must be home by now. (断定他已到家) 2.He ought to/should be home by now.(不太肯定) 3. This is where the oil must be.(直爽) should have done “本应该做某事而没做”。 表示对过去动作的责备、批评。 如：You should have finished your homework.你应该已经完成作业了。（事实上你没有完成。）4. This is where the oil ought to/should be.(含蓄)5.had better 的用法had better 意为“最好”，没有人称的变化，后面接不带to 的不定式，其否定形式为： had better not。如：We had better go now. 我们最好现在就走。You had better not give the book to him.你最好不要把这本书给他。二、 情态动词有具体的词义，但也同助动词一样，需要与其他词语一起构成句子的谓语，另外情态动词没有人称和数的变化，情态动词后必须跟动词原形。含有情态动词的疑问句1.由 can、may、must构成的疑问句（1）句式： Can/ May/ Must + 主语+动词原形+.？ 如：Can you repair the car? 你会修小汽车吗？Could he be a good student? 他能是名好学生吗？May I borrow your ruler? 我可以借你的尺子吗？Must we clean the room now?我们必须现在打扫房间吗？（2）对 may 引出的问句，可以有下列回答方式：Yes, of course. / Yes, certainly. / Sure .No, you mustnt. / No, you cant.（3）对must引出的疑问句，回答方式为： Yes, must. No, neednt/ dont have to.2.will， would， shall 的用法（1)will 在一般疑问句中表示客气的“请求、劝说”。 would 是will 的过去式，语气更加客气、委婉。 如：Would you show me your picture book? 你能让我看看你的画册吗？ Will you please give me a call? 请给我打个电话好吗？（2）对 will/ would you 的回答方式有以下几种：Yes, I will. (No, I wont.) / Sure . (Im sorry , I cant.)All right. / Certainly. (No, thank you .) / Yes, please.例 -Would you do me a favour and pass on my thanks to Lily?-_. A.Thats right B.With pleasure C.It doesnt matter D.No trouble解析 A. 意为“对了” ， B. 意为“ 乐意效劳”, C. 意为“ 没关系” D.意为“不费事”。 答案 B（3）shall引出的疑问句用于第一人称， 表示征求对方意见或客气的请求。 如：我给你把门打开好吗？ 我们现在开始好吗？其回答方式有以下几种：Yes, please. / All right. / No, thank you.3( C) 1 The children_ play football on the road. A. cant B. can C. mustnt D. must(A ) 2 You _ be late for school again next time. A. mustnt B. neednt C. dont have to D. dont need to( A) 3 -Must I do my homework at once? -No, you_. A. neednt B. mustnt C. cant D. may not4(D) 1 His arm is all right. He_ go and see the doctor. A. has not to B. dont have to C. havent to D. doesnt have to( B) 2 He had to give up the plan, _ he? A. did B. didnt C. does D. doesnt( C) 3 They had to walk here, _ they? A. mustnt B. did C. didnt D. hadnt5(A ) 1 He had better stay here, _ he? A. didnt B. dont C. hadnt D. isnt(B ) 2 Youd better_late next time. A. not to be B. not be C. wont be D. dont be(C ) 3 Youd better _ your hair _ once a month. A. had; cut B. had; cutted C. have; cut D. have; cutted(C ) 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 三、不同情态动词的否定意义也不同1.（1） cant可译为“不会”， 如：I cant play basketball. 我不会打篮球。（2）当句子表推测时，用cant 表达不可能， 如： He cant be ill. He is playing chess with Tom. 他不可能病了，他正和Tom 下棋呢。（3）cant 还可用来回答“ May I ? ” 这样的问句。 如： May I come in ? 我可以进来吗？ No, you mustnt. / cant. 不，你不能。（4）cant 还可用于固定习语中。如：She cant help crying. 她不禁大哭起来。2.may 的否定式为 may not ， 译成“ 可能不”， 如：He may not be at home. 他也许不在家。3.（1）mustnt 表示不许， 不可。如：He mustnt leave his room. 他不许离开他的房间。You mustnt talk in class. 你们不可以在课上说话。(2)mustnt 也可用于以 may 表示要求时的否定回答中。 如： May I stand here? 我可以站在这里吗？ -No, you mustnt(cant).不，不行。4.（1） neednt 意为“ 不必” 。 如：You neednt meet him unless youd like to.你不需要见他， 除非你愿意。 （2） neednt + have+ 动词的过去分词，表不需要完成但已完成的动作，暗含时间或精力上的浪费。如：You neednt have bought it. 你没必要买它（但你却买了）。5.shouldnt 表示不应该。 如： You shouldnt feel so unhappy over such little things. 对于这种小事，你不应该感到这么不高兴。 情态动词的被动语态含有情态动词的被动语态的结构为： 情态动词+ be + done (动词的过去分词)。做题时要兼顾情态动词和被动语态这两个方面。 如：You neednt get up so early every day.你不必每天都起这么早。She shouldnt speak t her mother in that way.她不应该用那种方式和妈妈说话。More and more trees must be planted in China.在中国必须种植更多的树木。Many of the stars can not be seen because they are far away from us.很多星星我们都看不到， 因为它们离 我们太远了。四、易混知识清单易混点一 can 和 be able to两者表示能力时用法相同， 但 can 只有原形 “can” 和过去式“ could ”两种形式，在其他时态中 要用be able to 来表示。 另外 be able to 常常指经过努力， 花费了时间和劳力之后才能做到某事。如：Jim cant speak English. 吉姆不会说英语。He could speak English at 5. 他五岁时 就会说英语。Well be able to see him next week.下星期我们将会见到他。He has been able to drive. 他已经会开车了。I m sure you ll be able to finish it quickly.我相信你能迅速地完成。We were able to reach the top of the mountain at noon. 我们能在中午到达山顶。易混点二 can和may1.can 和 may 均可用来征求意见或许可，意为“可以”， 一般可互换使用。如：Can/ May I help you ? 我能帮助你吗？2.can 和may 表示可能性时的区别：1)在肯定句中用 might， may， must， 不用can2)在疑问句中表示推测用 can，不用 might， may，must3)在否定句中用cant（不可能）， 不用 may， must。 如：She may be in the classroom . 她可能在教室里。Where can they be now? 他们现在可能在哪儿？That cant be true. 那不可能是真的。易混点三 may be 和maybe 用法 区别 常用位置may be may为情态动词， be为动词原形句中，作谓语maybe 副词，大概、也许，相当于perhaps 句首，作状语He may be wrong , but Im not sure. 也许他错了，但我也不确定。易混点四 cant 和 mustnt1.cant 根据其基本用法可译为：（1）不会， 如：I cant speak English . 我不会说英语。（2）不能， 如：We cant do it now because its too dark. 天太黑了， 我们现在干不了。 （3）不可能， 如：那个人不可能是咱们老师， 他年轻得多。The man cant be our teacher because he is much younger than our teacher.2. mustnt 意为“ 禁止、不许”， 用来表达命令，表示强烈的语气。 如：You mustnt play football in the street. Its too dangerous.你不可以在街上踢足球， 太危险了。易混点五 must 和 have to1.must 侧重于个人意志和主观上的必要， 还可以在间接引语中表示过去的 必要或业务。2.have to 侧重于客观上的必要，可用于现在时、过去时和将来时。如：I know I must study hard. 我知道我必须努力学习。My brother was very ill, so I had to call the doctor in the mid-night. 我弟弟病得厉害， 我只得半夜里把医生请来。I havent got any money with me, so Ill have to borrow some from my friend. 我身上没带钱，只好向朋友借点了。He said they must work hard. 他说他们必须努力工作。易混点六 need， dare 的两种用法need ， dare 作情态动词是， 多用于否定句、疑问句中，后接动词原形。如：You neednt explain it to me . 你不必向我解释这件事。 Dare you say that again? 你敢再说一遍吗？在肯定句中， 它们后边多接动词不定式，此时为实义动词。如：Tom needs to fetch the book for me .汤姆需要给我取回那本书。 Mary dared to go across the street by herself. 玛丽敢自己过马路。易混点 七 used to do / be used to doing / be used to do used to do 表示过去常常发生的动作， 强调过去，只用于过去，注意用 to do，不用doing形式；而be used to doing 意为“习惯做”， be 可有各种时态； be used to do 意为“被使用去做,” 为被动语态形式。如： My father used to eating meat.我父亲过去起床晚，但现在不得不早起了。She is used to eating meat.她习惯吃肉。He wasnt used to eating in a restaurant.他不习惯在饭店吃饭。Knives are used to cut things.刀是被用来切东西的。（被动语态）测试内容出现频率较高的情态动词主要集中在 can， may， must， need 等的用法上， 重点为以下四点:1.can ， could 表能力的用法。2.常见情态动词的提问和回答， 尤其是 May I ？ No，you mustnt/ cant. Must I ? No, you neednt/3.表示推测的用法， 肯定句中用may （可能）， must （一定）， 否定句中用may not（可能不）， cant（不可能）。注意 cant 与mustnt 的区别。4.情态动词的被动语态。例 1. _ you pass me a pen? Id like to write down the phone number. Sure. Here it is.A. Can B. Need C. Might D. Must 【解析】 由题干可知，本句表示请求、许可。【答案】 A例2. May I go to the cinema, mum? Certainly, but you _ be back by 11 oclock. A. can B. may C. must D. need 解析 由题意可知， 此处并非表推测的用法， 而是妈妈对孩子提出的要求， 故选C, 意为“ 必须”。 答案 C 例3. You _ get there by bus.A. dont need B. neednt to C. dont need to D. need dont to【解析】 由选项A 可知 need 为实义动词， 故应加上to 才正确。 选项 B neednt为情态动词， 应去掉to， 故选 C. 答案 C例4. You _ worry about me. Its nothing serious. A. cant B. mustnt C. neednt D. wont【解析】 由题干 Its nothing serious 可推断，第一句意为“你不必为我担心”， 故选C。 本题易错选B, mustnt 意为“禁止”，故不正确。 答案 C错题透视错因一 语境理解错误例5.Excuse me. Is this the right way to the Summer Please? Sorry, Im not sure . But it _ be. A. might B. can C. should D.could分析 考查情态动词might 表推测的用法。 “Im not sure” 说明说话者的语气并不肯定， 所以要用 might。 答案 A【错因透视】 情态动词表示推测时， 肯定句中用 might ， may， must， 其肯定程度递增。错因二 否定形式混淆例6. The man in the office_be Mr. Black because he went home just now.A.mustnt B.may not C.cant D.neednt【分析】 由下文 he went home just now 可知，作者判断办公室里那个人（不可能是Mr. Black 。 mustnt 意为“千万别”， may not 意为 “可能不”， neednt意为“不必”。cant 意为不可能， 故选C。 答案 C 【错因透视】 情态动词的否定式含义不同，要牢记每个否定式的不同含义。错因三 相似词语混淆例7.-Can you go surfing with us this afternoon?-Id like to , but I _ look after my sister at home , because my mother is ill.A.need B.must C.have to D.should【分析】 由题干my mother is ill 为客观要求可知， 答案 C错因透视 相似词组must 表示主观愿望，have to 则为客观要求。 学生由于不清楚这一点而误选B项。错因四 疑问答语 易错解例8. -May I take this book out of the reading room?-_. Please read it here.A. Certainly B.No, you neednt C.No, you mustnt D.No, you may not【分析】 May I ? 的否定答语为 No, you cant/ mustnt. ; Must I ?否定答语为 No，you neednt/dont have to.; Can I ? 的否定答语为 No， you cant. 在口语交际中， 要体会句子中的情感差别。【答案】 C课后练习题：情态动词练习题1 He had better stay here, _ he? A. didnt B. dont C. hadnt D. isnt2 Youd better_late next time. A. not to be B. not be C. wont be D. dont be3 Youd better _ your hair _ once a month. A. had; cut B. had; cutted C. have; cut D. have; cutted4 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 the History Museum next Sunday? A. Here you are B. Sorry, I cant C. Yes, please D. Let me try2 -Why dont you ask Mike to go with us? -Thanks, _. A. I will B. I wont C. lean D. I may3 -_ I take the newspaper away? -No, you mustnt. You_read it only here. A. Must; can B. May; can C. Need; must D. Must; must71 Excuse me. _ you please pass me that cup? A. Do B. Should C. Would D. Must2 _ you like to have another try? A. Could B. Will C. Would D. Do3 -Would you like to go boating with us?-Yes, _. A. Id like B. I want C. Id like to D. I do81 You_ worry about your son. He will get well soon. A. neednt B. cant C. mustnt D. have to2 The poor man needs our help, _ he? A. need B. neednt C. does D. doesnt3 -Must we do our homework first?-No, you_. You may have a rest first. A. mustnt B. neednt C. may not D. cant1.ADABB 2.CDBCA 3.CAA 4.DBC 5.ABCC6.CAB 7.CCC 8.ADB情态动词专项练习题1. - Where is Mary? - She _ in the library.She told me she wanted to borrow some books from the library. A. should be B. must be C. can be D. must have been2. His room is dark. He must _ to bed. A. go B. be going C. have gone D. have been gone3. “Will your father stay home tonight?” “Im not sure, He _to work.” A. must go B. can go C. may be gone D. may be going4. “Where is Tom?” “He isnt here I think he _ have gone home.” A. may B. must C. might D. A or B or C5. “I think Helen is at home.”“ No, she _ be at home, for she phoned me from the airport just five minutes ago.” A. mustnt B. neednt C. cant D. darent6. Hes late. What _ have happened to him? A. can B. may C. should D, must7. “ _ he be watching TV now?” Yes, he _ be watching TV now.” No, he _ be watching TV now.” A. Must; can; mustnt B. Can; must; cant C. Must; must; cant D. Can; can; mustnt8. -“_ he have left yesterday?” -Yes, he _ yesterday.” -No, he _ yesterday.” A. Must; must have left; cant have left B. Can; can have left; cant have left C. Can; must have left; cant have left D. May;