情態(tài)動詞語法講解

1、關(guān)于情態(tài)動詞語法講解第一張，PPT共四十四頁，創(chuàng)作于2022年6月情態(tài)動詞（modal verbs)： 表示說話人的語氣或情態(tài)，如請求、命令、愿望、能力以及可能性等。英語的情態(tài)動詞有：第二張，PPT共四十四頁，創(chuàng)作于2022年6月 can/could may/might must shall/should will/would need have to 能夠可能必須應該意愿敢需要不得不+ 動詞原形第三張，PPT共四十四頁，創(chuàng)作于2022年6月第四張，PPT共四十四頁，創(chuàng)作于2022年6月一、情態(tài)意義表示法1.表示“能力”和“可能” a)表示“能力”，可用can, could, be able

2、to can既能表示現(xiàn)在的能力，也表示將來的能力。Eg.Look! I can do it. I cant do it now, but I can do it later.第五張，PPT共四十四頁，創(chuàng)作于2022年6月現(xiàn)在“能力”：can, be able to As I have got enough money, I can/am able to help her.Can: 某樁具體事情：eg.I can climb this cliff.泛指一般的“能力”： He can drive a car. She cant play the piano.第六張，PPT共四十四頁，創(chuàng)作于2022

3、年6月將來“能力”：通常 will/shall be able to Ill be able to speak German in another two months具體某事：can Can you go and see him tomorrow morning? If I can, I will do it.第七張，PPT共四十四頁，創(chuàng)作于2022年6月過去“能力”: could, was/were able to 肯定句：Could：一般能力 She could play the piano when she was only six. was/were able to(及managed

4、 to)：具體事件 He was able to translate the article without a dictionary.第八張，PPT共四十四頁，創(chuàng)作于2022年6月 I talked a long time, and in the end managed to make her believe me.在否定句中，could既可以表示過去一般能力，也可表示過去某具體事情的能力. I couldnt/wasnt able to play the piano when I was at school.第九張，PPT共四十四頁，創(chuàng)作于2022年6月b)表示“可能”，可用may, mi

5、ght, can, could may/might：既可以表示現(xiàn)在的可能，也可表示將來的可能，might在口氣上比may更委婉現(xiàn)在：It may/might be true.將來：He may/might leave tomorrow.2.在疑問句中，用can，不用may。Can they have missed the bus?Yes, they may have.第十張，PPT共四十四頁，創(chuàng)作于2022年6月may not重音落在助動詞上，表示“不可能”，重音落在否定詞上，表示“不許可” , 比較：He may not go tomorrow.He may not go tomorrow.

6、所以在書面語中，表示“不可能”常用cant第十一張，PPT共四十四頁，創(chuàng)作于2022年6月can/could表示現(xiàn)在的可能，口氣上could比較委婉Thats not mine. Whose can it be?It could be Johns.can常用于否定句和疑問句，而could不受此限。If you dont have a guide, you could lose your way.It cant/couldnt be true.Can/could the news be true?第十二張，PPT共四十四頁，創(chuàng)作于2022年6月在肯定陳述句中，may與can的比較：Can指邏輯上

7、的可能性，may指事實上的可能性 The road can be blocked.(按邏輯可能會堵，)The road may be blocked.(可能現(xiàn)在正堵著，事實上) Mr Reed is in poor health. He can be ill at any time. Mr Reed looks pale. He may be ill.第十三張，PPT共四十四頁，創(chuàng)作于2022年6月“may/might +have done/have been doing”,“can/could +have done”表示過去的可能。He may/might have missed the t

8、rain.She may/might have been expressing her true feelings at that moment.She cant/couldnt have missed the train.“might/could +have done ”可以表示本來可能發(fā)生但沒有發(fā)生的，或者本來可能完成卻沒有完成的動作，You might have finished the work last week.I could have passed the examination, but I failed.第十四張，PPT共四十四頁，創(chuàng)作于2022年6月2表示“許可”和“不許”

9、 a)請求對方“許可”可用can, could, may, might. may/might較正式，could/might較委婉表示給予“許可”通常用can/may,而不用could/might Could I use your phone? Yes, of course you can. Might I trouble you for a light? You may indeed.第十五張，PPT共四十四頁，創(chuàng)作于2022年6月b)表示“不許”可用may not或者cannotCan I go out for a moment?No, you cant. May I use your ca

10、r for a few days?No, you may not. may not也可表示根據(jù)一般規(guī)定的“不許可”，而不是說話人不許可Borrowers may not take out of the library more than two books at a time. may not表示“不許可”的過去式不是might not He may not go.(=I dont permit him to go.)He might not go.(=Possibly he will not go.)過去的不許可：He was not allowed to go.第十六張，PPT共四十四頁，

11、創(chuàng)作于2022年6月3表示“義務”和“必然”a)表示“義務”，可用should, ought to, must. 表示要求，命令時，語氣由ought to、 should、must漸強Should/ought to表示“應該”，帶有敦促，勸說之意，可交替使用，前者語氣更強。You should/ought to drink less.Should/ought to +have done:本應該You should/ought to have asked my permission first.Must表示敦促或命令，必須。I really must stop smoking.第十七張，PPT共

12、四十四頁，創(chuàng)作于2022年6月表示將來的“必須”，常用have to的一定形式（will/shall have to) 比較：We must do it again.(表示現(xiàn)在)Well have to do it again.(表示將來)表示過去的“必須”，常用had toI had to leave at six yesterday.must有兩種否定形式:第一個是must not,表示“不許”、“禁止”,相應的半助動詞是be to的否定形式be not toYou mustnt talk like that.You are not to talk like that.(不許你如此講話。)

13、第十八張，PPT共四十四頁，創(chuàng)作于2022年6月第二個否定形式是neednt,表示不必。與neednt相當?shù)膭釉~形式是dont need to/dont have to/havent got toA: Must you leave soon?B: No, I neednt/dont need to/dont have to/havent got to.必須：must與have tomust側(cè)重于說話人的主觀意志 have to側(cè)重客觀需要 He must say it in English. (I want him to do so.)He have to say it in English.

14、 (He doesnt know Chinese.) 在特定語境中，用will也可表示“義務”，常用于第二人稱主語，這實際上是強化的祈使句。You will wait outside the gate.Brian! You will close the door.第十九張，PPT共四十四頁，創(chuàng)作于2022年6月b)表示“必然”，可用should，ought to和must(一般用于陳述句)，其中must口氣最為肯定。都指說話人根據(jù)一定情況做出推測或判斷.She should be here in a minuteThese young trees ought to provide shade

15、in ten years .All men must die.ought to(表示“推測”）的否定形式是oughtnt toYou oughtnt to have any difficulty getting the tickets.第二十張，PPT共四十四頁，創(chuàng)作于2022年6月如果是推測過去的事態(tài)，則用must +have doneYou must have left your handbag in the theatre.表示推測的must的否定形式是cant不是must notIf Fred didnt leave home before five, he cant be there

16、 yet.第二十一張，PPT共四十四頁，創(chuàng)作于2022年6月4表示“預見”和“推測”a)表示“預見”，即表示“單純將來”，可用will/shall+不定式，shall用于第一人稱，will用于第二、三人稱?，F(xiàn)在一般will可用于一切人稱表“將來”I will be a different person when I live in England.You will be hearing from me.She will probably last longer than you will.It will rain tomorrow.非正式語體中，will常用語第一人稱主語表將來，常用will、

17、shall的縮寫ll，模糊了其界限。Ill come in after church and give you a hand.第二十二張，PPT共四十四頁，創(chuàng)作于2022年6月b)表示“推測”，除用should, ought to,和must外，還可用will/would（語氣僅次于must）。They should/ought to be home by now.(他們現(xiàn)在該到家了)They would be home by now.(他們現(xiàn)在大概到家了)They will be home by now.（我估計他們現(xiàn)在一定到家了）They must be home by now.（他們現(xiàn)在

18、一定到家了）第二十三張，PPT共四十四頁，創(chuàng)作于2022年6月will/would表示“推測”可有三種情況 1）對特定事態(tài)的推測 A: Whos that man over there? B: That will be George, no doubt. C: That would be George, I except.2）對某些習慣性事態(tài)的推測，will指現(xiàn)在習 慣，would指過去習慣He will work all day without a rest.Before his retirement he would catch the early bus every morning.3）

19、對某些不受時限的客觀過程的推測，只用will,表示現(xiàn)在時間，可與一般現(xiàn)在時的類似用法交替使用。 Pigs will eat anything.=Pigs eat anything.第二十四張，PPT共四十四頁，創(chuàng)作于2022年6月5表示“意愿”、“意圖”和“決心”，a)表示意愿都可用will, would, shall。 will用于一切人稱的主語,可縮寫，will相當于be willing to ,I will lend you the money if you need it.My sister will help you with the luggage.You can help me

20、if you will.Will用于第二，三人稱的疑問句，是詢問別人是否愿意做某事，請求Will you please open the door for me?此時，will=would you, would you please, would you be good enough to ,would you like to, would you be so kind as to表示接受請求時，用will不用wouldWould you lend me your pen a minute?Certainly, I will.第二十五張，PPT共四十四頁，創(chuàng)作于2022年6月表示不愿意，用wi

21、ll not/wontI will not do anything solely for money.表示過去的意愿或者不愿意用would, wouldnt,間接引語I asked him if he would help me with my writing.shall一般用于第二、三人稱主語，表示說話人的意愿,而不是句子主語的意愿，在疑問句中表示征詢聽話人的意愿You shall stay with us as long as you like=Im willing to let you stay with us as long asHe shall be praised if he wo

22、rks hard for the people=Ill see that he is praisedShall you take a holiday this summer?第二十六張，PPT共四十四頁，創(chuàng)作于2022年6月b)表示意圖，同上a)用法一致。c)表示決心，同上shall表示“決心”時，否定形式為shall not /shant，表示說話人禁止、威脅No one shall stop me.第二十七張，PPT共四十四頁，創(chuàng)作于2022年6月6其他情態(tài)意義should可在某些語境中表示惋惜、憂慮、歡欣、驚訝等感情色彩。例如在某些that-分句，慣用的疑問句和感嘆句中。 How sho

23、uld I know?That he should dare to attack me!還可用在某些語境中并不表示具體的情態(tài)意義。例如在be-型虛擬式中或狀語分句中。I insisted that he go/should go with me.They got warmly dressed for fear that they should catch cold.此外，should還可以和say，think搭配表示婉轉(zhuǎn)口氣。I should say he is just the right man for the job.第二十八張，PPT共四十四頁，創(chuàng)作于2022年6月b) would可用

24、于委婉的簡述，客氣的請求,委婉的建議I dont think he would be so careless.(委婉的陳述)Would you like to stay here for the night?(客氣的請求)Wouldnt it be better for us to start off a little earlier tomorrow morning？(委婉的建議)第二十九張，PPT共四十四頁，創(chuàng)作于2022年6月c)作為情態(tài)動詞表示“膽敢”，dare通常只用于否定陳述句和疑問句,I dare not go there.多用于現(xiàn)在時形式，但它既可以指現(xiàn)在時間，The pres

25、idet was so hot-tempered that no one dare tell him the bad news.也可指過去時間。否定形式為darent。 Tom wanted to come, but he darent. dare用作主動詞，通常用于否定句和疑問句。 He does not dare (to) answer. dare的過去式dared通常只用于文學語言等正式語體，也還是用于否定意義。Nobody dared lift their eyes from the ground.第三十張，PPT共四十四頁，創(chuàng)作于2022年6月d) need表示“必須，需要”，做情態(tài)

26、助動詞，只用于否定句和疑問句，He neednt worry about it.作情態(tài)助動詞，答語肯定，must；否定，neednt Need we work late today? No, but we must tomorrow. Need I tell Elizabeth at once? No, you neednt tell he just yet. 詢問對方是否需要，必須做某事，可用need，也可用must, 否定用neednt或dont have to A: Must I see a doctor at once? B: No, you neednt/dont have to s

27、ee a doctor for the time being.第三十一張，PPT共四十四頁，創(chuàng)作于2022年6月Neednt +have done，表示過去本來不必做的事卻做了You neednt have bought that house.Didnt need to 與neednt have +-ed比較：I didnt need to go to the station.(因無必要不曾前往)I neednt have gone to the station.(本無必要卻在過去某時去了)e) used to(只有過去時形式，沒有現(xiàn)在時形式）表示過去習慣動作或狀態(tài)，這種狀況已不復存在。 He

28、 used to live in Shanghai, usedt he?在否定陳述句或否定疑問句中，用didnt use to或usedt to均可。He didnt use to smoke cigarettes=He usednt to smoke cigarette. 在肯定疑問句中有兩種形式： Used you to ?/Did you use to?Used you to go to the same school as Edward?=Did you use towould表示“習慣”時，可與used to交替使用，區(qū)別在于would只與動態(tài)動詞連用，通常用于正式語體。第三十二張，

29、PPT共四十四頁，創(chuàng)作于2022年6月17.2 情態(tài)助動詞的推測性用法和非推測性用法第三十三張，PPT共四十四頁，創(chuàng)作于2022年6月 uncertain might may could can should ought would will certain must 第三十四張，PPT共四十四頁，創(chuàng)作于2022年6月2能作推測性用法的情態(tài)助動詞的句法特征a)氣候的不定式可以采取完成體形式Y(jié)ou must have thought about it.b)其后的不定式可以采取進行體形式He must be calling tonightc)可以用于there-存在句There must be s

30、ome mistaked)其后的不定式為一般形式（即非完成體或進行體形式）時通常是靜態(tài)動詞He must be theree)主語可以是表示無生命物的名詞詞組It must be George.第三十五張，PPT共四十四頁，創(chuàng)作于2022年6月3能作推測性用法的情態(tài)動詞與所指時間1)直接引語中，說話人的主觀看法總是以現(xiàn)在時間 為基點的。2)說話人所推測的事件所發(fā)生的時間，要根據(jù)不定式所采取的形式而定。 不定式若為非完成體形式則表示現(xiàn)在時間或?qū)頃r間；不定式若為完成體形式則表示過去時間。 He must be there.=Im sure he is there. He must have go

31、ne.=Im sure he has gone. went.第三十六張，PPT共四十四頁，創(chuàng)作于2022年6月能夠(表能力)可以(表允許)必須主語 + can + 動詞原形主語 + may + 動詞原形主語 + must + 動詞原形主語 + cannot/ cant + 動詞原形主語 + may not + 動詞原形主語 + must not/ mustnt + 動詞原形Can + 主語 + 動詞原形？May + 主語 + 動詞原形？Must + 主語 + 動詞原形？Yes, 主語 + can.No,主語 + cant.Yes, 主語 + may.No,主語 + may not.Yes, 主

32、語 + must.No,主語 + neednt.在口語中可用can代替，但may更禮貌。第三十七張，PPT共四十四頁，創(chuàng)作于2022年6月1.My elder brother _(能) drive a car. 否定句：一般疑問句：肯定回答：否定回答：就劃線部分提問：Practice canMy elder brother cannot/cant drive a car.Can your elder brother drive a car?Yes, he can.No, he cant.What can your elder brother do?第三十八張，PPT共四十四頁，創(chuàng)作于2022年

33、6月2.You _ (可以) leave now. 否定句：一般疑問句：肯定回答：否定回答：就劃線部分提問：Practice mayYou may not leave now.May I leave now?Yes, you may.No, you may not.When may I leave?第三十九張，PPT共四十四頁，創(chuàng)作于2022年6月3.Lily _ (必須) go to the library. 否定句：一般疑問句：肯定回答：否定回答：就劃線部分提問：Practice mustLily mustnt go to the library.Must Lily go to the l

34、ibrary?Yes, she must.No, she neednt.Where must Lily go?第四十張，PPT共四十四頁，創(chuàng)作于2022年6月A.用must(not), may(not), can(not)填空：1.I dont understand this word. _ I use your dictionary? -Yes, please use it.2.The traffic light is turning red. We _ stop.3.You _ borrow two books at a time.4.Tom _ play table tennis, but he _ play football.5.Doctor, _ I take much medicine? -No, you neednt. But you _ drink a lot of water.6.Tom is good at drawing. He _ draw wonderful pictures.7.You _ smoke here. Its dangerous.8.-May I turn on the TV? No, you _.