語法專項復(fù)習(xí)情態(tài)動詞ModalVerb.ppt

語法專項復(fù)習(xí)： 情態(tài)動詞 (Modal Verbs),常用的情態(tài)動詞,can （could） may（might） shall（should） will （would） must（must） dare （dared） need （need）,have to ought to be able to used to had better,(1) 表示能力: can / could 只能表示現(xiàn)在或過去的能力。 *be able to 能用于各種時態(tài)。 *was / were able to : “設(shè)法做成某事” 相當于 managed to do sth. succeeded in doing sth.。,1. can ( could),(2)表允許，征求意見 Can/ Could I use your phone? *could語氣上比can更委婉,客氣。,can ( could),(3)表猜測，一般用于否定句和疑問句中： He cant be in the library now. Can it be Mr. Green?,can ( could),(4)表某人或某物一時的特點，表示“有可能， 有時會”。 Children can be naughty. It can be very warm in this area.,can ( could),You cant praise him too much. You cannot be over careful.,cannot cant 與tooover等詞連用，意思是 “越越”,“無論怎樣 也不為過”,(1.) 表示允許或請求允許。 You may keep this one, but you mustnt keep that one. May I speak to Janet? * might 表示現(xiàn)在時態(tài)的請求允許或允許，但語氣比may更委婉,客氣。 You might study in our room. Might I give you a piece of advice?,may,May,2. may (might),(2.)表示猜測(只能用在肯定,否定句中)如： She may be on her way home at this moment. She may not like this place. *might可以表示過去時態(tài)的“可能”。如： She told me she might come tonight. I am afraid she might think it was just a joke. *表示現(xiàn)在時態(tài)的“可能”，might語氣比may 弱。如： He might know her address. Be careful , you might fall down.,may (might),(3.)表示祝福,如： May you succeed! May you live long!,may,may / might well動詞原形或 may/ might as well動詞原形,“還不如，不妨，還是的好”,We may / might as well have something to eat .,3. must,(1.)表示“必須”，如： We must think , and well find a way out. 否定式mustnt , 表示“禁止”，“不許”。 如： You mustnt stay here. Its dangerous. *回答用must提問的句子，要用neednt作為否定回答，意為“不必”。 Must I stay in bed all day? No, you neednt / dont have to. Yes, you must.,3. must,(2.)表示猜測，只能用在肯定句中，如： He must be at home now.,must,* must有一種含義：“偏要”“硬要”。 表示說話人對句子主語所發(fā)出的動作或行為是不希望的、不滿的甚至是生氣的。 Why must you be so stubborn ? Why must you be so late ？,have to 也可以表示 “必須”，但： have to強調(diào)客觀需要，“不得不”; must更強調(diào)說話人的主觀看法, “必須”. (2) have to 有較多的時態(tài)。如： You will have to go back to school to receive continuing education. You dont have to do it. 比較：You mustnt do it.,(1.)用于一，三人稱,表示說話人征求對方意見 Shall Li Ping clean the classroom? Shall we have a break?,4. shall,(2.)用于二，三人稱,表示說話人給對方的命令，警告，允諾，威脅，決心等語氣,*You shall get a prize from me. *Each citizen shall carry his identification card when travelling. *You shall arrive there before sunset . *If you dont behave yourself,you shall be punished. *Nothing shall prevent from us working hard.,5. should,(1) You should stay here. (2) They should be there by now, I think. (3) You are mistaken, I should say. (4) Ask Tom to ring me up if you should see him. (5) Why should you be so late?,表勸告和建議，應(yīng)該,表推測，按道理應(yīng)當，估計,表說話人的謙虛，客氣，委婉的語氣，用于第一人稱,用于條件句中，表 “萬一”,表語氣，譯為 “竟然”,ought to (oughtnt to ),(1)表示 “應(yīng)該” You ought to take care of him. (2)表示推測 He ought to be home by now.,(1) If you will listen to me, Ill give you some advice. (2) Will/ would you please pass me the book? (3) Fish will die without water. If the pure water is heated to 100 , it will boil. (4) The machine wont work.,6. will / would,表意志和意愿,表請求，建議,表習(xí)慣性動作, “總是，慣于”,表功能， 意為 “能，行”,7. used to (usednt to / didnt use to),表示“過去常?！?* used to 即可以強調(diào)過去的習(xí)慣性動作(由動態(tài)動詞表示)，也可以強調(diào)過去的事實或狀態(tài)(由靜態(tài)東此表示)，且與現(xiàn)在形成對比;,* would 只強調(diào)過去特定情況下的習(xí)慣性動作(由動態(tài)動詞表示)，單純的過去和現(xiàn)在無關(guān).,I used to like opera，but now Im not interested in it.,She would sit there for hours sometimes ,doing nothing at all .,8. need,作為情態(tài)動詞時主要用在否定句和疑問句中: He neednt do it now. Need we begin right now?,He needs to do it now. Do we need to begin right now? You dont need to hand it in.,9. dare (darent),表示 “敢; 敢于”, 主要用于疑問句, 否定句和條件從句中, 一般不用于肯定句,Dare you go alone there? The boy darent say so before the teacher. How dare he do such a thing?,情態(tài)動詞短語的使用:,would like to do would rather do would prefer to do. had better do.,最好做,想做,了解情態(tài)動詞的完成式用法 (情態(tài)動詞+have done) 表示對過去情況的猜測或虛擬,表示對過去發(fā)生事情的推測用： must/may/might/cant /couldnt + have done,She passed the exam. She must have worked very hard before the exam.,They cant have finished the work so soon yesterday.,She may/might have left before I came here.,用于虛擬語氣的情態(tài)動詞:,should/ ought to have done shouldnt / oughtnt to have done might / could have done neednt have done,本應(yīng)該做（但事實沒做） 本來不應(yīng)