高中英语必修三情态动词语法.doc

高中英语必修三情态动词（ unit 1 ，unit 2）一、情态动词的特点:1.没有人称和数的变化。2. 有些情态动词有过去式的变化:e.g. will would , can could , may might , dare dared二、情态动词的否定式: 情态动词+ not +动词原形can not: cant , must not: mustnt , need not : neednt三、情态动词的用法及相互区别, 是考试的内容之一1. can , be able to be able to 表示经过努力后, 能够做到; be able to 有多种形式的变化。can 1). 表示体力或脑力方面的能力; 2). 表示允许、可能性。could 是can的过去式, 表示过去有能力及过去存在的可能性 ; 用于疑问句表示委婉地提出问题。1) The fire spread through the hotel very quickly but everyone _ get out. (NMET 97 )A. had toB. wouldC. couldD. was able to 2) -Will you stay for lunch? -Sorry, _. My brother is coming to see me. (NMET99)A. I mustntB. I cantC. I needntD. I wont 2.may 表示询问或说明一件事可不可做; 表示某事有可能发生。might是may的过去式; 用在疑问中比may委婉、客气。1) -May I take this book out of the reading-room?-No, you mustnt. ( Yes, you may.)2) -Might I make a suggestion? -Yes, you may.3. must 1). 表示必须要做的事: 必须 2) 表示很有把握的推断: 一定, 准是。have (has)to : have (has)got to 必须, 不得不。过去式: had to3) -Must I get to the station before three oclock?-Yes, you must. ( No, you neednt. )4) Im afraid you will have to wait a while.5) She must be in the classroom now.6) Mary _ be in Paris, I saw her in town only a few minutes ago. (NMET 94)A. mustnt B. shouldnt C. cant D. may not4. shall 1) 在疑问句中, 用于第一、三人称表示说话人征求对方的意见或向对方请求。2) 用于二、三人称,表示说话人给对方的 命令、警告、允诺等概念。1) - Shall I place an order with you now? -No, you neednt. -Shall he turn down the radio a bit? -Yes, please.(No, please dont.)2) You shall have the English book as soon as I finish it.3) Everything that he owns shall be taken away from him.4) Your brother seldom comes to see you, _?A. does heB. doesnt heC. will heD. isnt he5) Its a fine day. Lets go fishing, _?A. wont we B. will we C. dont we D. shall we5. should 应该 ; 应当1) You should listen to the doctors advice.2) You should study the article carefully.6. will, would1) 在疑问句中用于第二人称,表示说话人向对方提出请求或询问。用would语气更加婉转。2) will 表示现在的习惯性动作或状态; would 表示过去的习惯性动作或状态。3) will 用于各种人称, 表示 意志、意愿、决心、允诺; would 表示过去时间的 意志、意愿、.。(1) Dont smoke in the meeting room, _ you? A. do youB. will youC. can youD. could you-Will you come with me? -Yes, I will.(I am sorry , I cant.)(2) -Would you tell us something about yourself? -Yes, I will.(3) - Its my birthday tomorrow. Dont forget to come to my party.- _ .A. I dont B. I wont C. I cant D. I haven7. ought to 应该; 应当1) You oughtnt to smoke too much.2) She _ for what she has done.A. ought to praiseB. ought be praisedC. ought to have praisedD. ought to be praise8. dare 1. dare to come 2. dare come1) He dare not tell the truth. 2) He doesnt dare to come out at night.3) I dont know whether he _ try.A. dareB. needsC. wantsD. is allowed9. need 1). 作为情态动词:必须 2). 作为实义动词: 需要A.主语是人 need( to do something ; to be done by somebody) B. 主语是事物 need ( doing; to be done) 1) -Do they need to take any books with them?-No, they dont need to.2) -Need we buy any new equipment? -No, we neednt.3) This farm tool needs repairing. This farm tool needs to be repaired. 4) -Shall I tell John about it ?- No, you _ . Ive told him already.A. neednt B. wouldnt C. mustnt D. shouldnt5) Its a fine day. You _ take a raincoat with you. A. cant B. mustnt C. neednt D. may not情态动词 + 不定式的完成式是高考的考试要点1、must have done,“一定做过/一定已经”，表示对过去情况极大把握地推测，仅用于肯定句2、may/might have done 也许做过某事（推测）；本来可以做某事却没做3、cant have done 为否定句或疑问句,对过去的推测“不可能，一定没做过某事” could have done本来可以做某事却没做4. neednt have done 表示”不必要做某事，但做了”，而neednt do 则表示”不必做(也没做)”5.、ought to /should have done 表示”本来应当做的却没做” oughtnt / shouldnt have done 本来不应该做某事却做了6、would/could/might/should + have done 用来表示与过去事实相反的虚