情態(tài)動詞 (2)

1、PAGE PAGE 13情態(tài)動詞知識梳理情態(tài)動詞有具體的詞義，但也同助動詞一樣，需要與其他詞語一起構(gòu)成句子的謂語，另外情態(tài)動詞沒有人稱和數(shù)的變化，情態(tài)動詞后必須跟動詞原形?？键c一：can，may，must 等情態(tài)動詞在陳述句中的用法：1. can 的用法：（1）.表示能力、許可、可能性。 表示能力時一般譯為“能、會”， 即有種能力，尤其是生來具備的能力，此時may 和must 均不可代替它。如：She can swim fast, but I cant . 她能游得很快，但我不能。I can see with my eyes. 我用眼睛看。（2）.表示許可，常在口語中。如：You can us

2、e my dictionary. 你可以用我的字典。（3）.表示推測，意為“可能”， 常用于否定句和疑問句中， 此時cant 譯為“ 不可能”。 如：Can the news be true? 這個消息會是真的嗎？Can it be our teacher?那個人有可能是我們老師嗎？No, it cant be our teacher. He is on a visit to the Great Wall.不可能。咱們老師正在游覽長城呢。注意：can 用于肯定句，表示理論上的可能性，即事件或情況可能發(fā)生但并不涉及是否真的發(fā)生，譯為“有時會”，如：Driving on the snowy roa

3、ds can be very dangerous .【例題】( )I think Miss Gao must be in the library. She said she would go there. No. She _be there, I have just been there. A.cant B.mustnt C.neednt D.wouldnt2. could的用法：（1）.can的過去式，意為“ 能、 會”，表示過去的能力。如：He could write poems when he was 10. 他十歲時就會寫詩。（2）. could在疑問句中，表示委婉的語氣，此時 cou

4、ld 沒有過去式的意思。如:Could you do me a favour? 你能幫我個忙嗎？Could I use your pen? 我能用一下你的鋼筆嗎?Yes, you can.可以。（注意回答，表示給予允許，一般只用can）你知道can / be able to 的用法區(qū)別嗎？ 3. may/ might的用法：（1）.表示請求、許可，比can 正式，might 的語氣更加委婉。如：May/ Might I borrow your bike? 我可以借你的自行車嗎？Yes,you may. （注意回答，表示給予允許，一般只用can）You may go home now. 現(xiàn)在你可

5、以回家了?！纠}】( ) _ I borrow your MP3? Sure . Here you are. A. May B.Should C.Must D. Would(2) .表示推測，談?wù)摽赡苄?，意為?可能， 或許”，一般用于肯定句和否定句中。 如：It may rain tomorrow . 明天可能會下雨。She may be at home. 她可能在家呢.比較： cant 不可能 It cant be true .may not可能不 It may not be true .(3) may的過去式為might ，表示推測時?？赡苄缘陀趍ay。 如：He is away fro

6、m school. He might be sick.他離開學(xué)校了，可能是他生病了。你知道m(xù)ay be /maybe 的用法區(qū)別嗎？4. must的用法：(1).must 表示主觀看法，意為“必須、一定”。 如：You must stay here until I come back.在我回來之前你必須呆在這兒。Must I hand in my homework right now? 我必須現(xiàn)在交作業(yè)嗎？(2) 其否定形式mustnt表示“ 一定不要 ” “千萬別” “禁止, 不許”. 如：You mustnt play with fire. 你不許玩火。You mustnt be late

7、. 你一定不要遲到。（3）對must引導(dǎo)的疑問句，肯定回答為must，否定回答為neednt 或 dont have to .如：Must I finish my homework?我現(xiàn)在必須完成作業(yè)嗎？No, you neednt.不，你不必。(4)must表示有把握的推測，用于肯定句。如: The light is on, so he must be at home now.燈亮著，他現(xiàn)在肯定在家。你知道m(xù)ust/ has to 的用法區(qū)別嗎？ 5. need的用法：（1）.need 表示需要、必須，主要用于否定句和疑問句中，其否定形式為neednt，意為“沒有必要，不必”。 用need

8、提問時，肯定回答為 must，否定回答為 neednt或dont have to。 如： Need I stay here any longer? 我還有必要留在這兒嗎？Yes, you must .是的。No. you neednt /dont have to. 不， 你不必。(2).need 還可以作實義動詞，此時有人稱、數(shù)和時態(tài)的變化，如果是人作主語后邊多接動詞不定式。如：I need to do it right now. 我需要馬上做這件事。He needs to learn more about the girl.他需要多了解那個女孩。6. dare 的用法：dare意為“敢、敢于

9、”, 用法近似于need，有兩種詞性：（1）dare 作為情態(tài)動詞，多用于否定句、疑問句或條件句中，無第三人稱單數(shù)形式，只有一般現(xiàn)在時和一般過去時。如：Dare he tell them what he knows? 他敢告訴他們所知道的情況嗎？I darent ask her this question . 我可不敢問她這個問題。（2）dare 作為實義動詞，此時有人稱、數(shù)及時態(tài)的變化。如：He doesnt dare to break his promise.他不敢食言。7. shall 的用法：shall表示征求對方意見（多用于第一、三人稱）. 如：Shall we go out for

10、 a walk? 我們出去散步好嗎？在英語中，我們可以用其他多種方式提出我們的建議或征求對方意見。(1).用“Lets do.”來提出建議。如：Lets go for a walk after supper.(2).用“What/How about.?”來提出建議；about后接名詞或動詞ing形式。如：What about/How about a drink? What about/How about taking Tom with us?(3).用“Why not.?”來提出建議，表示“何不”not面后接動詞原形?！癢hy not.?”實際上是“Why dont you/we.?”的簡略形

11、式。如：Why not meet at the school gate at eight? Why dont we stay here another day?(4).用“Would you like.?”來提出建議，意思是“你想要嗎?”Would you like后可接名詞或不定式。如：Would you like a cup of tea?Would you like to go and see her?因此，如果我們說：“去游泳好嗎?”英語中可有這樣幾種表達法：Shall we go for a swim?Lets go for a swim，shall we?What about/Ho

12、w about going swimming?Why not go for a swim?Would you like to go for a swim?What do you think of going for a swim?8. should /ought to的用法：（1）should 意為“應(yīng)該” ，可表示勸告、建議、義務(wù)、責(zé)任等。 如：We should protect the environment. 我們應(yīng)該保護環(huán)境。(2) ought to (= should)否定形式：ought not to / oughtnt to 一般疑問形式 將ought 提前。 People ou

13、ght to stop polluting the environment .9. will/would 的用法：will表示現(xiàn)在的意愿、意志、打算，可用于多種人稱。如：I will help you if Im free this afternoon.今天下午如果我有空，我就會幫你。would表示過去的意愿、意志、打算。如：The doctor said he would fight against SARS until his end of life.注意：1、will在there be句型中的形式及其句式變換。 由于“一般將來時”的結(jié)構(gòu)可以用“will+動詞原形”來表示，所以there

14、be句型的一般將來時的形式就是there will be。（一定不能說there will have）例如： There are many students in our school. There will be many students in our school. There will be a sports meeting next week. 一定不能說：There will have a sports meeting next week.2、will 與be going to do sth區(qū)別：. be going to 表示近期、眼下就要發(fā)生的事情，will 表示的將來時間則較

15、遠一些，如：He is going to write a letter tonight. He will write a book in the future . be going to 表示根據(jù)主觀判斷將來肯定發(fā)生的事情，will表示客觀上將來勢必發(fā)生的事情。He is seriously ill. And he is going to die. He will be twenty years old. . be going to 含有“計劃，準備”的意思，而 will 則沒有這個意思，如： She is going to lend us her book. He will come her

16、e in half an hour. .在有條件從句的主句中，一般不用 be going to, 而多用will, 如： If it doesnt rain tommorrow, Ill go to the park with you .10. had better 的用法：had better 意為“最好”，沒有人稱的變化，后面接不帶to 的不定式，其否定形式為：had better not。如：We had better go now. 我們最好現(xiàn)在就走。You had better not give the book to him.你最好不要把這本書給他?？键c二:不同情態(tài)動詞的否定意義也

17、不同：1.（1）.cant可譯為“不會”， 如：I cant play basketball. 我不會打籃球。（2）當句子表推測時，用cant 表達不可能， 如：He cant be ill. He is playing chess with Tom. 他不可能病了，他正和Tom 下棋呢。（3）cant 還可用來回答“ May I ? ” 這樣的問句。 如：May I come in ? 我可以進來嗎？No, you mustnt. / cant. 不，你不能。（4）cant 還可用于固定習(xí)語中。cant help doing 禁不住，情不自禁 cant wait to do sth 迫不及待

18、如：She cant help crying. 她不禁大哭起來。The children cant wait to open the box. 孩子們迫不及待地想打開盒子。2. may的否定式為 may not，譯成“ 可能不”.如：He may not be at home. 他也許不在家。3.（1）mustnt 表示不許，不可。如：He mustnt leave his room. 他不許離開他的房間。You mustnt talk in class. 你們不可以在課上說話。(2) mustnt 也可用于以 may 表示要求時的否定回答中。如：May I stand here? 我可以站在

19、這里嗎？No, you mustnt (cant). 不，不行。4.（1）neednt 意為“ 不必”。如：You neednt meet him unless youd like to.你不需要見他，除非你愿意。5. shouldnt 表示不應(yīng)該。如：You shouldnt feed the goldfish so much food .考點三: 情態(tài)動詞表示推測的用法:一、“情態(tài)動詞+動詞原形”表示對現(xiàn)在的推測。1、can表示推測時一般用于否定句或疑問句。如：That man cant be her husband , she is still single.Who is knockin

20、g at the door?Can it be the postman?2、must表示肯定的推測，一般用于肯定句中。如：He must be in his office now. for the lights in his office are still on.3、might 表示推測時不一定是may的過去時，只是表示其可能性較小。如：The man may be the headmaster.Where is Mr Li? He might be working in his office. 4、Could表示推測時，語氣can比要弱，說話者留有余地。如：Could it be an a

21、nimal?It could not be , because it is not moving.【情態(tài)動詞易混點歸納】易混點一: can和be able to:兩者表示能力時用法相同，但can只有原形“can”和過去式“could”兩種形式，在其他時態(tài)中 要用be able to 來表示。另外 be able to 常常指經(jīng)過努力，花費了時間和勞力之后才能做到某事。如：Jim cant speak English.吉姆不會說英語。He could speak English at 5. 他五歲時 就會說英語。Well be able to see him next week.下星期我們將會見

22、到他。He has been able to drive. 他已經(jīng)會開車了。Im sure youll be able to finish it quickly.我相信你能迅速地完成。We were able to reach the top of the mountain at noon.我們能在中午到達山頂。易混點二: may be 和maybe 用法區(qū)別 常用位置may be may為情態(tài)動詞， be為動詞原形 句中，作謂語maybe 副詞，大概、也許，相當于perhaps 句首，作狀語例如：He may be wrong , but Im not sure. 也許他錯了，但我也不確定。

23、 Maybe he is 30 years old . = He may be 30 years old .易混點三：cant 和 mustnt1. cant 根據(jù)其基本用法可譯為：（1）不會。如：I cant speak English . 我不會說英語。（2）不能。如：We cant do it now because its too dark.天太黑了，我們現(xiàn)在干不了。（3）否定句中表示推測。“不可能”，如：The man cant be our teacher because he is much younger than our teacher. 那個人不可能是咱們老師，他年輕得多。

24、2. mustnt 意為“ 禁止、不許”， 用來表達命令，表示強烈的語氣。 如：You mustnt play football in the street. Its too dangerous.你不可以在街上踢足球，太危險了。易混點四：must 和 have tomust 側(cè)重于個人意志和主觀上的必要。have to 側(cè)重于客觀上的必要，可用于現(xiàn)在時、過去時和將來時。如：I know I must study hard.我知道我必須努力學(xué)習(xí)。My brother was very ill, so I had to call the doctor in the mid-night.我弟弟病得厲

25、害， 我只得半夜里把醫(yī)生請來。2. have to可以用于多種時態(tài)；如：The composition is due to hand in this morning, so I had to finish it last night. 作文今天早晨到期，因此我不得不昨天晚上完成。His mother is ill, so he has to look after his mother at home .【情態(tài)動詞例題解析】1、_ you pass me a pen? Id like to write down the phone number. Sure. Here it is.A. Can

26、B. Need C. Might D. Must2、May I go to the cinema, mum? Certainly, but you _ be back by 11 oclock.A. can B. may C. must D. need 3、You _ get there by bus. A. dont need B. neednt to C. dont need to D. need dont to4、You _ worry about me. Its nothing serious. A. cant B. mustnt C. neednt D. wont5、Excuse m

27、e. Is this the right way to the Summer Please? Sorry, Im not sure . But it _ be.A. might B.mustnt C.cant D.must6、The man in the office_be Mr. Black, because he went home just now.A.mustnt B.may not C.cant D.neednt7、Can you go surfing with us this afternoon? Id like to , but I _ look after my sister

28、at home , because my mother is ill.A.need B.must C.have to D.should8、May I take this book out of the reading room? _. Please read it here.A. Certainly B.No, you neednt C.No, you mustnt D.No, you may not【情態(tài)動詞活學(xué)巧練】11 John_ come to see us tonight, but he isnt very sure yet. A. may B. canC. has to D. mu

29、st2 They _ do well in the exam. A. can be able to B. be able toC. can able to D. are able to3 May I take this book out? No, you_. A. cant B. may not C. neednt D. arent4 You_ go and see a doctor at once because youre got a fever.A. can B. must C. dare D. would5 Can you speak Japanese? No, I_. A. must

30、nt B. cant C. neednt D. may not21 He_ be in the classroom, I think. No, he _ be in the classroom. I saw him go home a minute ago. A. can; may not B. must; may not C. may; cant D. may; mustnt2 Shall I get one more cake for you, Dad? Thanks, but you_, Ive had enough.A. may not B. must not C. cant D. neednt3 Even the top students in our class cant work out this problem, so it be very difficult.A. may B. must C. can D. need4 He isnt at school. I think he _ be ill. A. can B. shall