高中情態(tài)動詞講解

情態(tài)動詞專項講解1. China is developing its high-speed train technology fast, so it _be good enough to catch up with the best. A. may B. might C. must D. should2. Then some other interesting reasons appear, such as “Its so smoggy that I _find my way to office.A. mustnt B. wont C. cant D. shouldnt3. The world is big, and I want to see it, wrote a teacher in her resignation letter. _ you quit your job to travel the world? A. Must B. Might C. Should D. Would 【答案揭曉】CCD一、情態(tài)動詞的定義情態(tài)動詞是一種本身有一定的詞義，但要與動詞原形或其被動語態(tài)一起使用，給謂語動詞增添情態(tài)色彩，表示說話人對有關行為或事物的態(tài)度和看法，認為其可能.應該或必要等。情態(tài)動詞后面加動詞原形。1. No driving electric motorbikes in some areas is a rule that we shall obey in Fuzhou. 必須.一定（法律.法規(guī)等） 動詞原形2. Women who are exposed to second-hand smoke during their pregnancy can be at risk of abortion.能，會，可以(表示有能力或機會) 動詞原形二、常考情態(tài)動詞的關鍵用法(一) can1. Jim，it is time you went to bedYou need to get up early tomorrow.Its not fair，Mary can stay up till ten hut I have to go to bed at eight.可以(表示允許)2.If it were not for the fact that she cant sing，I would invite her to the party.能，會，可以(表示有能力)3. Luckily, iron can be reworked and mistakes dont have to be thrown away能夠，可以(表示某事物的特點)4.Peter can be really difficult to get along with at times even though hes a nice person in general. 有可能;有時會5. I cannot choose but to go.不能，無法 (用于否定句，表示情況不允許)6.I cannot thank you enough,it has been a wonderful day. 再.也不為過 ( 也可以用can never/hardly.too much)7.Is Jack on duty today?It cant be him.Its his turn tomorrow.不可能 (can可用于否定句/疑問句中表猜測，此句表對現(xiàn)在的猜測)8.Can he have been chosen as captain of the football team? Yes, he must have. 可能 （can可用于否定句/疑問句中表猜測，can have done表示對過去的猜測猜測）9. This old lady was struggling out of the train and I said, Oh, can I help you?能 (通常用于疑問句，表示建議或提議幫忙)10. Can you just lift the table for a second?(用于疑問句時,can 表示禮貌的請求，而 cant 表示強烈請求） (二) could1.For my return journey, I felt I could afford the extra and travel first class能;會 (表示發(fā)生在過去的能力)2.I feel bored with nothing interesting to do.-You could watch TV. There will be a very good Hollywood film on this evening.可以(表示提議或建議)3. Could I have a look? -Of course you can. 表許可（委婉的語氣用could，回答時用can）4. An improvement in living standards could be years away.可能(表示某事可能屬實或可能發(fā)生，對將來或者現(xiàn)在發(fā)生事情的肯定猜測)5.When the ship sailed out from Thailand, the 16 sailors on board couldnt have thought_ that only half of 可能 (could have done，只用于否定句和疑問句中，表示對過去發(fā)生事情的猜測)them would return again. 高.考.資.源.網6. He did not regret saying what he did but felt that he could have expressedit differently.(could have done用于肯定句中，表虛擬語氣，表示過去本有可能發(fā)生的事情但卻并未發(fā)生，不能使用 cant have done的形式)（三）be able to1.Even if standardized tests like the SAT could show a students academic proficiency（學業(yè)水平）,they will never be able to test things like confidence, efforts and willpower, and are unable to give us the full picture of a students potentialities（潛力） 【解析】be able to 解釋為“能夠”，有各種時態(tài)的形式。注：can 和be able to 都可以表示能力.can泛指一般的能力,而且只有兩種形式,即:can, couldbe able to 則主要指具體做到了某件事的能力，其形式主要是靠be 發(fā)生變化，所以形式比can 多可以說：I can swim. I am able to swim. 但是不能說：All the people could escape from the big fire in time. 只能說：All the people were able to escape from the fire in time.(四) may1.Every one of us may plant a tree in the school, or organize a thorough cleaning on the campus.可以(表許可)2. （1）Some people who dont like to talk much are not necessarily shy；they may just be quiet people.有可能，也許(may表猜測，用于肯定或否定句中，此例表示對現(xiàn)在某種情況的猜測）（2）You might just as well tell the manufacturer that male customersmay not like the design of the furniture. 也許，可能(may表猜測，用于肯定或否定句中，may not 為“可能不”的意思)（3）I cant find my purse anywhere.Youmay have lost it while shopping.(may表猜測，may have done表示對過去或者現(xiàn)現(xiàn)在已經完成的動作的肯定猜測) 3.May God bless you! 祝;但愿(五) might1.I was wondering if I might ask you a favor? 可不可以，能否(用于禮貌地打斷別人.提出問題.做出請求或引出接下來要說的話)2.Excuse me.Is this the right way to the Summer Palace? Sorry，I am not sure.But it might be.可能(表不是很有把握的猜測，語氣比may 弱)3.Where is my dictionary? I remember I put it here yesterday.You might have put it in the wrong place.(might表猜測，might have done則表示對過去或者現(xiàn)已完成的動作的肯定猜測=may have done)4. I told your friend how to get to the hotel，but perhaps I might have driven her there.（此處，might have done表虛擬語氣，意為“過去原本可能/可以做到的事而未做”）5.This holiday isnt much fun; we mightmay as well be back home.只好(做);(做)也無妨(六) will1.The low test score, they think, will make it impossible for them to get into a good college.將（表示將來）2.You will carry out these instructions and report back into this afternoon.(表示將來的正式安排)3.He will become her senior adviser- her deputy, if you will.愿意4.-Anyone, answer the phone? - I will. 臨時的決定5. Mary will sit for hours reading. The window will not open, however hard he tries. 表現(xiàn)在經常反復的動作或者趨向6. Man will die without air.表必然性(七) would1.John promised his doctor he would not smoke，and he has never smoked ever since.（will 的過去式，用于轉述）將2.Hurry up! It would be a shame to miss the beginning of the play.Shed be a fool to accept it.將，將會(表示判斷或看法)3.She wouldnt change it even though she knew it was wrong.不愿(表示意愿) 4.When he had a problem to solve，he would work at it until he found an answer. 常常（表示過去的習慣）She would be always the first to offer to help. The car wouldnt start this morning.老是，總是（表趨向） (八) shall1.We/I shall call you back this afternoon.(表將來用于No.1人稱)2.- Has Mr. Tom White arrived? - Yes, already. Shall he wait outside or just come in? (shall用在疑問句中，且主語為No.1/No.3人稱，表示征求對方意見)3.（1）What does the sign over there read?“No person shall smoke or carry a lighted cigarette，cigar or pipe in this area.”（2）“The interest shall be divided into five parts，according to the agreement made by both sides，”declared the judge.（3）You shall get the answer tomorrow.（4）They shall not be allowed in after 11 p.m. (shall用在陳述句中，且主語為No.2/No.3人稱時，表示允諾、命令、警告、決心或規(guī)定)(九) should/ought to1. I think Ill give Bob a ring. You should. You havent been in touch with him for ages.應該;應當2. (1) Margaret should not stay at home all day long in front of the TV.應該，必須(表示給出指示或公布官方命令)(2) That s rightShe ought to go to the fitness center with us. 應該，必須3.There should not be any difficulty about passing the road test since you have practised a lot.應該，可能 (表示預期或可能性)4.If you should be fired, your health and pension benefits will not be automatically cut off將要，假定要 (用在虛擬條件從句中表示事件發(fā)生的可能性)5.I insisted that we should have a look at every car應該(用在某些動詞、名詞之后that引導的虛擬語氣從句中) 6. Its surprising/strange that he should be a thief. 竟然 （用在某些adj./n. 之后that 引導的虛擬語氣中）7.Ill tell Mary about her new job tomorrow.You should have told her last week. (should have done=ought to have done， 表示本應該做的事而未做)8.You oughtnt to have been late for yesterdayS class meeting，as it was so important (ought not to have done=should not have done，表示過去本不該做的事卻做了) 注：ought to與 should的用法區(qū)別如下1. 一般說來，兩者可替換，只是ought to語氣稍重。如：You ought to/should go and see Mary. 你應該去看看瑪麗。2. 表示出于法令規(guī)則、行為準則、道德責任等客觀情況而“應該”做某事時，一般應用ought to，若用should則強調個人意見、主觀看法。如：We ought to go and see Mary tomorrow, but I dont think we will. 明天我們按理應該去看看瑪麗，但是我認為我們去不了。 (此句不宜用should)。3. 在公告、須知或條例中，出于禮貌，常用should. 如：You should not run alongside the swimming-pool. 不準在游泳池邊奔跑(十) must/ have to1. Its the office! So you must know eating is not allowed here. Oh, sorry.必須，應當 (通常因為規(guī)定或法律)2. In crowded places like airports and railway stations， you must take care of your luggage.務必，一定要 (用于表示建議或邀請)John，look at the time. Must you play the piano at such a late hour?偏偏，非要 (用于問句中表示生氣)4. Tom，you mustnt leave all your clothes on the floor like this!一定不要Hi, Tom. AnyideawhereJaneis? She_must be_intheclassroom. Isawhertherejustnow.很可能是，想必是，肯定是(must表猜測，只用于肯定句中，此句是對現(xiàn)在的猜測)Guess what？ I have got A for my term paper.Great!You must have read widely and put a lot of work into it. (must have done表示據已知情況對過去情況進行肯定的推測，只用于肯定句中)Some aspects of a pilots job can be boring，and pilots often have to work at inconvenient hours.必須，不得不What do you think we can do for our aged parents?You dont have to do anything except to be with them and be yourself.不必【解析】have to和must1) 兩詞都是必須的意思，have to 表示客觀的需要， must 表示說話人主觀上的看法，既主觀上的必要。My brother was very ill, so I had to call the doctor in the middle of the night. 我弟弟病得很厲害，我只得半夜里把醫(yī)生請來。(客觀上需要做這件事)He said that they must work hard. 他說他們必須努力工作。（主觀上要做這件事）2) have to有人稱.數.時態(tài)的變化，而must只有一種形式。但must 可用于間接引語中表示過去的必要或義務。He had to look after his sister yesterday.3） 在否定結構中： dont have to 表示不必 mustnt 表示禁止，You dont have to tell him about it. 你不一定要把此事告訴他。You mustnt tell him about it. 你一定不要把這件事告訴他。(十一) need/ dare1. What sort of house do you want to have? Something big?Well， it need not be bigthats not important.必要(need作為情態(tài)動詞只用于否定句和疑問句中)2. Catherine，I have cleaned the room for you.Thanks.You neednt have done it.I could manage it myself. (neednt have done 表示過去本不必做的事卻做了)3. I dare say you are British but you still need a passport to prove it.可能，大概;想必，我想【固定搭配】4. The goverment dare not raise interest rates again. 敢(dare作為情態(tài)動詞只用于否定句和疑問句中)5. How dare you talk to me like that? 竟敢(dare作為情態(tài)動詞只用于否定句和疑問句中)【解析】1.need/dare作情態(tài)動詞無人稱或數的變化， 后接動詞原形，多用于否定句和疑問句中，但I dare say 例外。2.need 作為行為動詞有人稱和數的變化， 后面可接名詞、代詞、動名詞及帶to 的動詞不定式；可用于肯定句、疑問句和否定句中。如：（1）She needs help.她需要幫助。（2）-Do I need to go at once? 我需要馬上走嗎？ 區(qū)別 Need I go at once?- Yes, you must. / No, you neednt.（3）It was Sunday and she didnt need to go to work. So she stayed at home. (后加to，實義動詞) She neednt have gone to work that day. She could have stayed at home.（后加原形，情態(tài)動詞）3.dare用作實義動詞，其后可帶動詞不定式，否定句中也可帶省to不定式，且有人稱和數以及時態(tài)的變化。例如： (1) I dare to jump down from the top of the wall. 我敢從那墻頭上跳下來。 (2) She doesnt/didnt dare (to) meet her teachers eyes. 她不敢與老師對視。 三、情態(tài)動詞重點用法小結表示猜測（可能性）詞形肯定式否定式疑問式must必然.必定/should按說應該/ought to按說應該/can/不可能有可能嗎？could微弱的可能不可能語氣比can弱may或許，也許，可能不/might比 may 還弱比may not 還弱/【注】對現(xiàn)在或者將來可能發(fā)生事情的猜測的結構為： must/should/ought to/cant/could/may/might + V(原形) 對過去可能發(fā)生事情的猜測的結構為： must/ cant/couldnt/may/might + have V-ed 例如：He may/might/must/should be on his way home now.(現(xiàn)在) I didnt hear the phone. I must have been asleep.（過去）情態(tài)動詞+have done情態(tài)動詞+完成式用法例句must have done(過去)想必/準是/一定做了否定為：cant/couldnt have doneIt must have rained last night, for the road is quite muddy.can/could not have done用于疑問句/否定句，表猜測，(過去)可能做了某事Can he have gone to his aunts?He cannot have forgotten it.could have done表虛擬，用于肯定句，“過去本可以做而未做”Tom could have done better in the exam.may/might （not）have done1.也許，或許（肯定句）2.可能不（否定句）3.表虛擬語氣，“(過去)本可以做到而沒做到”Its too late. I think he may have gone to bed.He may not have finished the work.You didnt do the work well that day. You might have done it better.should/ought to have done(過去)本該做某事，而實際上未做You ought to have done this exercise more carefully.should not/ought not to have done(過去)本不該做某事，而實際上做了You shouldnt have told her the truth.neednt have done(過去)本不必做某事而做了You neednt have taken a taxi there, for it was very near to my house.had better （not） have done(過去)最好（沒）做了You had better not have scolded me.would rather （not） have done寧愿(過去)（沒）做了I raised objections at the meeting, but now I would rather not have done that.would like/love （not） to have done(過去)本（不）打算做但未做成I would love to have gone to the party last night, but I had to work extra hours to finish a report.情態(tài)動詞解題技巧關鍵詞：一情，二境，三時(1) 認真審題，結合所給出的語境，正確把握說話者的語氣.情感.態(tài)度.觀點等。 (2) 認真思考所給選項中情態(tài)動詞的基本特征和用法，并結合語境推敲答案。 (3) 要注意把握時間概念。 例如： Thank you for all your hard work last week. I dont think we _ it without you. 過去 “（要）沒你” A. can manage B. could have managed C. could manage D. can have managed 根據題干中所給出的時間last week可知我們已經做完了工作，已經完成，故排除A.C兩項，再結合could (not) have done表示猜測可知說話者想表達的意思是：要沒你，我們不可能完成這項工作。故答案為B項。情態(tài)動詞經典考題1. I _ use a clock to wake me up because at six oclock each morning the train comes by my house.A. couldnt B. mustnt C. shouldnt D. neednt2. Im going to Europe on vacation together with John if I _ find the money.A. can B. might C. would D. need3. We _ the difficulty together, but why didnt you tell me?A. should face B. might face C. could have faced D. must have faced4. The new law states that people _ drive after drinking alcohol. A. wouldnt B. neednt C. wont D. mustnt5. Its q