modalverbs.ppt

1、Modal Verbs,介紹 用法&比較 表推測 表虛擬,介紹,1、情態(tài)動詞是一種本身有一定的詞義,表示說話人的情緒,態(tài)度或語氣的動詞,但不能單獨作謂語, 只能和其他動詞原形構成謂語。 2、情態(tài)動詞無人稱和數(shù)的變化, 情態(tài)動詞后面跟的動詞需用原形(M.V.+ do / be doing/have done),否定式構成是在情態(tài)動詞后面加 “not”。 個別情態(tài)動詞（can ,will,may,have to,dare,need）有現(xiàn)在式和過去式兩種形式。 3、過去式（might,could,would）用來表達更加客氣, 委婉的語氣, 時態(tài)性不強, 可用于過去，現(xiàn)在或?qū)怼?1. We can

2、 be there on time tomorrow. 2.May I have your name? 3.Shall we begin now? 4.You must obey the school rules. 5. How dare you treat us like that！ 6.He could be here soon. 7.Im sorry I cant help you. 8.He must have been away. 9.You should have told him the news yesterday. 10.Must you play the piano at

3、this time? It is so late now 11. When I was a child I would sit in front of the house ,waiting for my parents. 12. It is strange that he should have done that thing.,用法（本意）&比較,must 必須（命令），必定（推測） mustnt do 禁止做某事 e.g.1 I must finish my work today. 2.You mustnt work all the time. 3.Must I return the bo

4、ok tomorrow? 4.After such a long walk, you must be tired. 5.He must be the man I am looking for. 6. -Must we read this book tonight? - Yes, you must (No, you neednt.),must (主觀認為) Vs. have to（客觀所迫）,It is raining outside, so I _ take an umbrella. 2. _ I finish it now?,2. Can 能夠（能力,許可），可能（通常用于否定推測） can

5、t 1._ 2._ could 能夠(過去/現(xiàn)在：語氣委婉)，有可能（語氣較弱） e.g.1Can you pass me the books? 2.Could you help me, please? 3. It could be Marys as she likes green. 4. It cant be Mary as she is in America now.,can Vs. be able to 能與其他情態(tài)動詞連用的只能是be able to 2. be able to 更強調(diào)做成了，而can 指有能力但不一定成功 I am sure I will_ finish the jo

6、b soon. Finally he _ swim to the shore and was saved.,3. May 可以（許可，同意），可能（推測） may not 1._ 2._ might 可以（過去/現(xiàn)在：語氣委婉）有可能（推測，語氣較弱） 1.- May I come in? - Yes, you may(can). No you cant. 2. Might I borrow some money now? 3. He might be alive. 4. He may come here by train, but he has his own car.,4. Will 將要

7、，將會（將來時：決心，愿望）；愿意(will not 擬人用法) would 1._ 2._ 3._ e.g. 1. Ill do my best to catch up with them. 2. He said he would help me . 3. Would you please help me? 4. If he will help us, he will do it. 5. The door wont open. 6. When I was there, I would visit the cafe after work every day.,5. Should 應該（建議，命

8、令，要求）；按常理推測； 竟然（驚訝） 1.You should hand in the exercise book. 2.This should be no problem. 3.Why should I meet him？ 4. It is strange that he should have used up all the money intended for dog food. 5. The suggestion that we should start early is worth considering.,should (責任) Vs. ought to（義務） We _ fig

9、ht againt the bad deeds. The police _ fight against the bad deeds,6. Shall 1. 一、三人稱疑問句表征求對方意見 2.二、三人稱陳述句表威脅、命令、允諾、 規(guī)定 e.g. 1. When shall we go? 2. Shall he come in? 3. Lets go, shall we? 4. You shall get no money from me, if you go on doing that. 5. Anyone who steal the gold shall be put in prison.

10、6. You shall get a gift if you do it well.,7. need 需要與 dare 敢 實動(s, ed)：need to do dont need to do dare to do dont dare to do 情動（ed）: need(not) do dare (not) do need doing= need to be done e.g.1. I need a rest. 2.You need to clean the room every day _ 3. He doesnt need to clean the room every day._

11、4. He didnt dare to go out at night. _.,情態(tài)動詞表推測,不可能,必定,cant,must,might (not),may (not),could (not),1. 基本原則 can 用于否定句或疑問句 must 用于肯定句（陳述句） may might could 肯定句或否定句 e.g.- Can it be Mary? - Yes,it must be her. - No, it cant be her - Im not sure. It might/ may/ could be her. 注：Training by yourself can be

12、highly dangerous 時態(tài)問題 M.v. + do / be doing/ have done be +adj. be + n.,3. 關于反意問句 1. He cant be there now, _? 2. There must have been a village in the past ,_? 3. The children must have known the truth till now, _? 4. Mr. Wang cant have been here last night,_? 5. The man must be a thief,_?,情態(tài)動詞表虛擬(與事實相反),表虛擬語氣的情態(tài)動詞有：would , could , should, might （ought to , need ） 時態(tài)問題,e.g. 1. If he had time next week, he would take a few days off. 2.You neednt have told him about it.,M. v. + have done,m