（精心整理）情態(tài)動詞表推測的講解及練習題

1、九年級英語表推測語氣的講解與練習表推測時，英語中只使用must,may,might,may not和cant。這五個表達的語氣依次遞減：must:一定（語氣肯定）may：也許（不很肯定）might：或許（比may語氣更弱）may not：也許不（表否定）cant：一定不（must的反義）推測現(xiàn)在的事情用must,may,might,may not和cant+do或bee.g.She must be at home now. The boy may play now.推測過去的事情用must,may,might,may not和cant+have donee.g.She might have b

2、een ill yesterday. He must have hold the party.情態(tài)動詞must, can, could, may, might表推測的用法 情態(tài)動詞中的must, can, could, may, might都表推測。其中must的可能性最大，can / could次之，may / might最小。具體用法如下：1.must的用法（1）表示推測“可能性”時，意思是“一定、準是”，語氣較肯定，較有把握。He must be American. = It is certain that he is American. 他準是個美國人。（2）must表推測只能用于肯定

3、句。如果要表示“一定不、肯定不”的意思時，應(yīng)用cant,如詢問某種可能時，應(yīng)用can。He must know my address. 他肯定知道我的地址。（一定） He cant know my address. 他肯定不知道我的地址。（一定不）Can he know my address? 他知道我的地址嗎？（詢問可能性）（3）must表示推測時，可以推測現(xiàn)在/正在發(fā)生的動作/過去發(fā)生的動作。He must have a car now. （現(xiàn)在）他一定有輛小汽車。He must be doing his exercises in the classroom.（正在進行）他一定在教室里做練

4、習。He must have finished the work.（過去發(fā)生）他一定已完成了工作。注：must表示推測時很少用于將來的情況。一般不用He must come tomorrow.可用Its certain / Im sure that he will come tomorrow.（4）在反意疑問句中，當附屬部分含有表示推測意義的must時，疑問部分的助動詞應(yīng)與must后面的動詞在非推測情況下的用法保持一致。 He must be a worker, isnt he? （現(xiàn)在）他準是個工人，是嗎？It must have rained last night, didnt it? （

5、過去）昨晚一定下雨了，是不是？You must have learned English for many years, havent you? （完成時）你一定學了好多年英語，是嗎？2.can / could的用法（1）can表示推測“可能性”時，往往用于否定句或疑問句。Cant“一定不”，語氣很肯定。can在疑問句中意思是“會、可能”。用于肯定句時，表示理論上的，潛在的可能性（有傾向，實際上未必會發(fā)生或者不涉及實際是否發(fā)生）往往與sometimes 或者 someone 有關(guān)。Accidents can happen. He cant be at home. = It is impossi

6、ble that he is at home. 他一定不在家。（2）can /cant后可接進行時/完成時，表示對現(xiàn)在發(fā)生的動作或過去發(fā)生的動作進行推測。They cant be reading in the library. 他們一定不在圖書館讀書。He cant have gone to Shanghai for I saw him a minute ago. 他不可能去了上海，我剛才還看見他。Its so late. Where can she have gone? 天晚了，她可能去哪兒了呢？（3）在反意疑問句中，當陳述部分含有表示推測意義的cant時，疑問部分的助動詞應(yīng)與cant后面的

7、動詞在非推測情況下的用法保持一致.He cant be a teacher, is he? 他不是教師，是嗎？She cant have finished her homework, has she? 她一定沒有完成家庭作業(yè)，是不是？could可用于表示某事有可能發(fā)生表示可能性不大的推測。意思相當于may/might Dont eat it. It could be poisonous. 不要吃它，可能有毒。The plane could be delayed by fog. 飛機可能會因為霧晚點。 （5）could還可以用于表示客氣、委婉、禮貌的請求語氣。Excuse me, could y

8、ou tell me the way to the bus station?Could you help me?（6）couldnt表示否定推測，表示某事不可能真實，或由于特定事實或環(huán)境某事肯定不會發(fā)生。It couldnt possibly be poison. 這不可能是毒藥。表示對過去發(fā)生的事推測，常常和have done 連用He was not at home last night . He could/ might have gone to movies. I didnt see her at the meeting yesterday; she couldnt have spok

9、en at the meeting. 3. may和might的用法（1）may, might表示推測“可能性”時，意思是“可能”、“也許”，語氣沒有 must肯定。He may / might be American. = It is possible that he is American.他可能是個美國人。注：might不表示過去時態(tài)，只是語氣上比may更委婉，表示的可能性更小。（2）may, might表推測時，可以用于否定句，意思是“可能不、也許不”，但不用于疑問句。He may / might not be at home. 他也許不在家。（3）may, might可以推測現(xiàn)在正在

10、發(fā)生的動作或過去發(fā)生的動作。He may / might be sleeping now. （現(xiàn)在）他可能正在睡覺。The boy may / might not be watching TV at home. （現(xiàn)在）這個男孩可能沒在家看電視These students may / might have seen the film before.（過去）這些學生以前可能看過這部電影。（4）may, might還可以推測將來的情況。I think we should take raincoat with us, it may rain. 我想我們應(yīng)該帶上雨衣，可能要下雨了。She might

11、not come this afternoon. 她今天下午可能不來（一）情態(tài)動詞表推測的三種句式 能用于表推測的情態(tài)動詞：must, can, could, will, would, may, might, should, ought to1.在肯定句中一般用must (一定)，may（可能），might / could（也許，或許）。 （1）He must/may/might know the answer to this question? 他一定/可能/也許知道這個問題的答案。 （2）It is cold in the room. They must have turned off t

12、he heating. 屋里很冷，他們肯定把暖氣關(guān)了。 2.否定句中用cant / couldnt(不可能), may not/might not(可能不)。 （1）It cant/couldnt be the headmaster. He has gone to America. 這不可能是校長，他去美國了。 （2）He may not/might not know the scientist. 他也許不認識那位科學家。 3.疑問句中用can/could (能?)。 （1）Could he have finished the task? 他可能把任務(wù)完成了嗎？ （2）Can he be at

13、 home now? 他現(xiàn)在能在家嗎？ 注：以上三種句式中情態(tài)動詞的語氣按程度都是依次遞減的。Might, could并非may, can的過去式，而表示語氣較為委婉或可能性較小。（二）情態(tài)動詞表推測的三種時態(tài) 1.對將來情況的推測，用“情態(tài)動詞 + 動詞原形”。 （1）She must / may / might / could arrive before 5. 5:00前她一定/可能/也許到。 （2）She must/may/might/could walk miles and miles among the hills without meeting anyone. 她一定/可能/也許會

14、在山里一連走好幾英里而遇不到一個人。 2.對現(xiàn)在或一般情況的推測，用“情態(tài)動詞 + be”，“情態(tài)動詞 +be doing”或“情態(tài)動詞 + 動詞原形”。 （1）He must / may / might / could be listening to the radio now. 他一定/可能/也許正在聽收音機。 （2）He cant ( couldnt ) / may ( might ) not be at home at this time. 這個時候他不可能/可能不在家。 （3）Mr. Bush is on time for everything .How can ( could )

15、he be late for the opening ceremony ? 布什先生一向準時，這次開幕式他怎么可能遲到呢？ 3.對過去情況的推測，用“情態(tài)動詞 + have +過去分詞”。 （1）It must / may / might / could have rained last night .The ground is wet. 地濕了，昨晚肯定/可能/也許下雨了。 （2）The door was locked. He can ( could ) not / may ( might ) not have been at home . 門鎖著，他不可能/可能不在家。 （3）Can /

16、Could he have gotten the book？ 難道他找到書了嗎？ 注：情態(tài)動詞 should /ought to表推測時，意為“想必會，理應(yīng)”但與“have +過去分詞”連用時，則又可構(gòu)成虛擬語氣意為“本應(yīng)該做某事卻沒做”。例如： （4）Its seven oclock. Jack should/ought to be here at any moment. 現(xiàn)在七點鐘了，杰克理應(yīng)隨時到達。（推測） （5）She should / ought to have attended your birthday party, but she had to look after her

17、mother in hospital. （虛擬） 她本該出席你的生日晚會的，可是她得在醫(yī)院照顧她媽媽。 （6）Tom should not /ought not to have told me your secret, but he meant no harm. （虛擬） 湯姆本不該告訴我你的秘密，可是他并無惡意。補充強調(diào)：推測的句型特點（對某一次的推測句型有兩部分：語氣和時態(tài)）（1）語氣部分：（以下情態(tài)動詞語氣由強至弱） 肯定句：must、may、might（=could） 否定句：cant（=couldnt）、maynt、mightnt 疑問句：can、could（語氣更加委婉不確定）（2

18、）時態(tài)部分： be表示對現(xiàn)在的推測 have done表示對過去的推測 be doing表示對正在進行的推測u 語氣部分寫在前時態(tài)部分寫在后，組合在一起就是推測（三）幾組表推測的情態(tài)動詞用法“情態(tài)動詞完成時”是歷年高考的熱點，在做此類練習時，既需要掌握這一結(jié)構(gòu)的基本用法，又應(yīng)該仔細體會題干所提供的語言信息，準確理解語言環(huán)境和說話人的含義，尤其要注意題干中時態(tài)給予的暗示。1.must have done 表示對已經(jīng)發(fā)生的事情的推測，意為“一定，想必”, 句子中表示的是一種肯定的推測。這種結(jié)構(gòu)一般只用于肯定句，其否定形式是cant （couldnt）have done ，表示“不可能，肯定不會”。

19、例如：He didnt hear the phone . He must have been asleep. 他沒有聽到電話響，他肯定是已經(jīng)睡著了。He must have been to Shanghai. 他一定去過上海。They cant have gone out , because the light is on . 他們不可能出去，因為燈亮著。2. can（could）have done表示對過去的時間內(nèi)可能發(fā)生的事情的猜測，can have done 一般只用于否定句和疑問句。could have done 還可以用于肯定句，常用來表示本來可能完成而實際未完成的動作。例如：He

20、cant have finished the work so soon. 這項工作他不可能完成得這樣快。We could have walked to the station , it was so near . 我們本來是可以走到車站去的，路很近。3. may（might）have done （1）表示對已經(jīng)發(fā)生的事情的不太肯定的推測，意為“可能已經(jīng)，或許已經(jīng)”。（2）虛擬用法表示本可以做，但卻沒做（表示很委屈地責備）If we had taken the other road , we might have arrived earlier. 如果我們選擇另一條路，我們可能會到得早一些。He

21、 might have given you more help, he was very busy. 他本來是可以給你更多幫助的，盡管他很忙。4. neednt have done 指實際上做了本來不必要做的事，意為“本來不必”。例如：There was plenty of time . She neednt have hurried. 時間很充裕，她本不必匆忙。You neednt have told him the news. 他本來不必把這個消息告訴他。5. should （ought to ）have done 指本該做而實際未做的事，意為“本來應(yīng)該”。其否定式shouldnt（oug

22、htnt）have done 則表示某種行為不該發(fā)生但卻發(fā)生了。例如：You should have started earlier , but you didnt. 你本應(yīng)該早一點出發(fā)，但是你沒有。You ought to have helped him （but you didnt ）. 你本應(yīng)該幫助他。We shouldnt have waited for her because she never came. 我們本不應(yīng)該等她，因為她根本不會來。6.Would have done 本想做（卻沒做）wouldnt have done 本不想做（卻做了）I would have helpe

23、d you, but I was too busy.我本想幫你，但我太忙了。小試牛刀一、單項選擇1 John_ come to see us tonight, but he isnt very sure yet. A. may B. need C. cant D. must 2 John isnt in the classroom. He play soccer on the playground with Bob. A. can B. must C. should D. cant3 That _not be her husband . She is still single. A. may

24、B.can C. could D. might 4 You_ go and see a doctor at once because you got a fever. A. can B. must C. dare D. would5 -Can you speak Japanese? -No, I_. A. mustnt B. cant C. neednt D. may not 6 -He_ be in the classroom, I think. -No, he _ be in the classroom. I saw him go home a minute ago. Acan; may

25、not B. must; may not C. may; cant D. may; mustnt 7 -Is Lena swimming in the pool? -No, she swim. She is terrified of water.A. may not B. must not C. cant D. neednt8 He isnt at school. I think he _ be ill.A. can B. shall C. must D. might9 -What do you think “upset” means? - Im not sure. It mean “sad”

26、.A.may B. must C. can D. should 10 The children_ play football on the road. A. cant B. can C. mustnt D. must 11.The road is wet . It _last night.A. must rain B. must have rained C. could have rained D. can have rained 12 .He _you more help , even though he was busy .A might have given B might not gi

27、ve C may not have given D may give 練一練1. Look! The light is out in her room. She to bed already. A. must go B. had to go C.must have gone D.has gone 2. We had a wonderful time yesterday. You .Why didnt you come? A. had to come B.should have come C.might have come D.must have come 3. There were alrea

28、dy five people in the car but they managed to take me as well. It_ a comfortable journey.A. cant be B. shouldnt be C. mustnt have been D. couldnt have been4. My sister met him at the Grand Theatre yesterday afternoon, so he _ your lecture.A. couldnt have attended B. neednt have attendedC. mustnt hav

29、e attended D. shouldnt have attended5. I was really anxious about you. You _ home without a word.A. mustnt leave B. Shouldnt have left C. Couldnt have left D. neednt leave6. Oh, Im not feeling well in the stomach,I_ so much fried chicken just now.A. shouldnt cut B. mustnt have eaten C. shouldnt have

30、 eaten D. mustnt eat7. Mr.White _ at 8:30 for the meeting, but he didnt show up.A. should have arrived B. should arrive C. should have had arrived D. should be arriving8. You _ be tired - youve only been working for an hour.A. must not B. won t C. can t D. may not9. - Isn t that Anns husband over th

31、ere?- No, it _ be him -Im sure he doesnt wear glasses.A. cant B. must not C. wont D. may not10. There _ be any difficulty about passing the road test since you have practised a lot in the driving school.A . mustnt B. shant C. shouldnt D.neednt11. I was on the highway when this car went past followed

32、 by a police car. They _ at lease 150 km an hour.A. should have been doing B. must have been doingC. could have done D. would have done12. He _ have completed his work; otherwise, he wouldnt be enjoying himself by the seaside.A. should B. must C. wouldnt D. cant13. - The woman biologist stayed in Af

33、rica studying wild animals for 13 years before she returned.- Oh, dear! She _ a lot of difficulties!A. may go through B. might go throughC. ought to have gone through D. must have gone through14. This cake is very sweet. You _ a lot of sugar in it.Ashould put Bcould have put Cmight put Dmust have pu

34、t15. Catherine, I have cleaned the room for you.Thanks. You it. I could manage it myself.Aneednt do Bneednt have done Cmustnt do Dshouldnt have done16.Tom is never late for work. Why is he absent today?Something _ to him.Amust happen Bshould have happened Ccould have happened Dmust have happened情態(tài)動詞

35、+have done 結(jié)構(gòu)1-You didnt wait for Mr. Smith last night, did you?-No, but we _. He didnt return home at all.A. couldnt have waited B. neednt haveC. didnt need to D. should wait2Harry _ have won the Physics competition easily yesterday, but he gave up.A. could B. might C. should D. must3-May I speak t

36、o your manager Mr. Smith at six oclock tonight ?”-“Im sorry, Mr. Smith to a conference before then.”A. will have gone B. had gone C. would have gone D. has gone4-Tom took away our teachers cell phone without being permitted.- Really? I cant imagine that he _ have done such a thing.A. must B. may C. can D. should6The weather turned out to be fine yesterday. I_ the trouble to carry my umbrella with me .A. should have taken B. could have takenC. neednt have taken D. mustnt have taken7He paid for a seat, when he _ have entered free.A. could B. would C. must D. need8I di