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Modal Verbs情态动词 学习目标：学生学会can, could, may, might, will, would, shall, should, must, mustn’t的用法 一、情态动词的特征 1．有一定的词义，但不能单独作谓语，它们要和行为动词或连系动词连用，构成谓语。 2．没有人称和数的变化，主语是第三人称单数时，情态动词的形式不发生变化。 We/He must work hard． 3．后面接原形动词，即不带to的不定式（ought to, have to, used to本身带有to)。如： He may lose his way． / You ought to obey the law．你要遵守法律。 4．具有助动词的作用，即可用来构成否定句、疑问句及用于简明答语。 二．情态动词用法要点 ㈠ can (could) ⒈ 表示能力，could主要指过去时间。 ①Can you lift this heavy box? ②Mary can speak three languages. ③Could the girl read before she went to school? ⒉ 表示客观可能（理论上或是逻辑判断上）。 ①The temperature can fall to –60℃, that is 60℃ below freezing. ②Accidents can happen at any time. ③It can be interesting to go out for a walk. ⒊ 表示请求允许。 ①He asked whether he could take the book out of the reading-room. ②---Can I have a look at your new pen? --- Yes, you can. / No, you can’t. 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。 ⒋ 表推测。用于否定句、疑问句。（表惊异、怀疑、不相信等态度。） ①You could have done better, but you were too careless. ② I saw Mr. Wang just now. He couldn’t have gone toGermany. ③He can’t (couldn’t) be over sixty. 他不可能超过六十岁。 ⒌ 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 togo to the party yesterday evening in spite of the heavy rain. ㈡ may (might) 1表示请求和允许。might比 may语气更委婉，而不是过去式。 肯定回答：Yes, please. / Certainly. 否定回答：No, you mustn’t /can’t , / Please don’t ./ You’d better not. ----Might/ May I smoke in this room? ---- Yes, you can. (No, you can’t / mustn’t. ) 注意：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。 2 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. 3 may 放在句首，表示祝愿 ①May God bless you! ② May you succeed! 4.may/might as well 动词原形， '不妨，最好，满可以，倒不如'。相当于had better ①You may as well do it at once． ②We may as well stay where we are． ㈢ must ⒈ 表示必须、必要。 You must come in time. 注意答语： --- Must we hand in our exercise books today? --- Yes, you must. --- No, you don’t have to / you needn’t. mustn’t 表示明令禁止，“千万别，不许，一定不要” You mustn’t play with fire. ⒉表示推测、可能性（只用于肯定的陈述句） ①He must be ill. He looks so pale. ②Your mother must be waiting for you now. ③It must have rained last night, for the ground is wet. ⒊must 意为“偏偏，偏要，硬要”做某事，指的是做令人不愉快的事情。 ①Must you shout so loudly? ②---How old are you，madam? ---If you must know，I’m twice my son’s age. ⒋ 对比 must 和 have to 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 The play isn’t interesting, I really must go now. ② I had to work when I was your age. ㈣ will ⒈ 表意愿，愿望，决心。 ①If you will read the book, I’ll lend it to you. ②I will do anything for you. ⒉ 表请求，建议对方做某事。用于疑问句，与第二人称连用。 ①Will you close the window? It’s a bit cold. ②Won’t you drink some more coffee? 再来一点咖啡好吗？ ⒊ 表示某种倾向或习惯性动作。 ①Oil will float on water. ②Fish will die out of water. 鱼离开水就不能活。 ③The door won’t open. 这门打不开。 ④The boy will sit there hour after hour looking at the traffic go by. ㈤ would 1. 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。 ①Every time she was in trouble, she would go to him for help. ②The wound would not heal. 2. 表示估计和猜想。 It would be about ten o’clock when she left home. 3.表意愿。 Would you like some cake? （表示肯定含义的请求劝说时） I said I would do anything for you. 我说过我愿意为你做任何事。 4.表委婉地提出请求、建议或看法。 Would you mind cleaning the window? 请把窗户擦一下好吗？ ㈥ shall ⒈ shall 用于第一人称，表示提议或征求意见。 Shall I turn on the lights? / What shall we do this evening? ⒉ shall 用于第二、三人称，表示说话人给对方的命令、警告威胁、允诺或决心。 ① You shall fail if you don’t work hard. 表示：________ ②He shall have the book when I finish it. 表示：_______ ③You shall do as I say. 表示：_______ ④Nothing shall stop us from carrying out the plan. 表示：_______ 3. 表示宣布法律或规定。 According to the rules, each competitor shall wear a number over the race. 典型例题 1. -----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 2. John promised his doctor he _________ not smoke, and he has never smoked ever since. A. might B. should C. could D. would 3. Tom, you _____ leave all your clothes on the floor like this. A. can't B. mustn’t C. shouldn't D. needn't 4. --- What does the sign over there read? --- “No person ______ smoke or carry a lighted cigarette in this area.” A. may B. can C. shall D. should 5.---What’s the name? ---Khulaifi. _________ I spell that for you? A. Shall B. Would C. Should D. Can 6. It is usually warm in my hometown in March, but it _________ be rather cold sometimes. A. must B. can C. should D. would 7. 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 8.--- Cathy, I have cleaned the room for you. ---Thanks. You _____ it. I could manage it myself. A. mustn’t to B. needn’t do C. needn’t have done D. shouldn’t have done 9. Peter _______ be really difficult at times even though he's a nice person in general. A. shall B. should C. can D. must 10. You _________ be hungry already----you had lunch only two hours ago! A. wouldn't B. can't C. mustn't D. needn't 11.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 12.--- Tom came to work last Friday, but no one has seen him since. --- ________ he have had an accident ? A. Should B. Must C. Might D. Could 13.--- It’s the office! So you _______ know eating is not allowed here. --- Oh, sorry. A. must B. will C. may D. need 14.Although he was badly hurt, he _____ explain what had happened. A. could B. might C. was able to D. couldn’t 15. Peter ___come with us tonight, but he isn't very sure yet. A. must B. may C. can D. will 答案： BDBCA BBCCB BDACB |
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来自： zhounan214 > 《待分类》
