1 / 17 情态动词精品学案 情态动词解读: ① 本身有一定的词义，表示说话人的情绪、态度或语气的动词。 ② 不能单独作谓语。 ③ 和其他动词原形构成谓语。 ④ 谓语动词之前。 ⑤ 无人称和数的变化。 ⑥ 否定式构成是在情态动词后面加“not”。 ⑦ 个别情态动词有现在式和过去式两种形式，过去式可以用来表达更加客气、委婉的语气，时态性不强，可用于过去，现在或将来。 经典例句： We can be there on time tomorrow. 我们明天能按时去那儿。 May I have your name? 我能知道你的名字吗？ Shall we begin now? 我们现在就开始吗？ How dare you treat us like that! 你怎么敢那样对待我们! We can't carry the heavy box. 我们搬不动那箱子。 情态动词考点：

1. 情态动词表示推测。 2. 情态动词的基本用法。 3. 情态动词的答语。 2 / 17

常见情态动词： 情态动词有can (could), may (might), must, have to, shall (should, will (would), dare (dared), need (needed), ought to等。 情态动词的基本用法：

一、 can, could 1) 表示能力（体力、知识、技能）时，等于be able to 。 a) Can you lift this heavy box?（体力） b) Are you able to lift this heavy box? c) Mary can speak three languages.（知识） d) Is Mary able to speak three languages? e) Can you skate?（技能） 此时可用be able to代替。

2) can表示请求和允许。 -----Can I go now? ----- 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。（特别注明：这是在表示请求和允许的时候。）

---- Could I come to see you tomorrow? ---- Yes, you can. ( No, I’m afraid not. ) can't在否定句中可以表示命令，不允许，但是语气比mustn't弱，具有劝慰的意思. 3)can表示“有时会”： A kind person can lose temper sometimes. 4）表示与五种感官和知觉的动词连用。 I can hear/ see you clearly from here. You can imagine how annoyed she was ! 3 / 17

5）can 与be able to 的区别 ①Can只有一般现在时（can）和一般过去式（could）；而be able to则有更多的时态。 I’ll not be able to come this afternoon. ②当表示“经过努力才得以做成功某事(此事一般是一次性的，具体指的是某件事经过努力做成了)”时应用be able to，不能用Can。 经典例句：

He was able to go to the party yesterday evening in spite of the heavy rain. He was able to survive the fire because he was brave. 经典练习

1.(2010全国卷I 29). Just be patient .You_____________ except the world to change so soon. A. can’t B. needn’t C. may not D. will not 3. (2009北京卷) One of the few things you ___ say about English people with certainty is that they talk a lot about the weather. A. need B. must C. should D. can 4. The fire spread through the hotel very quickly but everyone __________ get out. A. had to B. would C. could D. was able to 5.【2012全国卷II】⒘ I’m going to Europe on vacation together with John if I ___ find the money. A. can B. might C. would D. need （2011四川卷）20. The police still haven’t found the lost child, but they’re doing all they ______. . A. can B. may C. must D. should 6、(2006湖南卷)32.Some aspects of a pilot’s job ________ be boring, and pilots often _______ work at inconvenient hours. A. can; have to B. may; can C. have to; may D. ought to; must 7. The biggest problem for most plants, which ______ just get up and run away when threatened, is that animals like to eat them. (07湖南) A. shan’t B. can’t C. needn’t D. mustn’t 4 / 17

二、 may, might （非高考重点，考查较少） 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can’t或mustn’t，表示“不可以，禁止”。 ----Might/ May I smoke in this room? ---- No, you mustn’t. ---- May/Might I take this book out of the room? ---- Yes, you can. (No, you can’t / mustn’t. ) 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）用于祈使句，表示祝愿。（May + 主语+动词原形） May you succeed! 经典例题：

(2010四川卷3). — I take the book out? — I'm afraid not. A. Will B. May C. Must D. Need 5 / 17

三、 must, have to 1) 表示“必须”；否定形式mustn’t，表示“禁止”。 You must come in time. You mustn’t tell anyone about this——it’s a secret. 2) 硬要；偏要 If you must drink so much , of course you’ll feel sick. 3 ) must 与have to 的区别：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。don’t have to =needn’t 经典例题： 1. (2005全国卷1)26. Tom, you leave all your clothes on the floor like this ! A. wouldn’t B. mustn’t C. needn’t D. may not 2. (2006浙江卷)19. — Could I have a word with you, mum? — Oh dear, if you ________. A. can B. must C. may D. should 3. In crowded places like airports and railway stations, you___ take care of your luggage. (2007北京卷) A. can B. may C. must D. will 4. — What do you think we can do for our aged parents? — You ________ do anything except to be with them and be yourself. (2007重庆卷) A. don’t have to B. oughtn’t to C. mustn’t D. can’t 6 / 17

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 I’m unfair? 2． He daren’t speak English before such a crowd, dare he? 3． If we dared not go there that day， we couldn’t 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。 1．You needn’t come so early. 2. ---- Need I finish the work today? ---- Yes, you must. / No, you needn’t. 3) dare和 need作实义动词用时， 有人称、数和时态的变化。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 doesn’t dare (to) answer. 3. He needs to finish his homework today. 经典例题：