2021年高考英語二輪復(fù)習(xí)考點(diǎn)講解：情態(tài)動(dòng)詞和虛擬語氣

1、第一部分、情態(tài)動(dòng)詞一、can/could與be able to1can/could用來表示“一般能力”；be able to有多種時(shí)態(tài)，且用來表示在特定條件下的“具體能力”。如：My grandma is over seventy，but she can still read without glasses.They will be able to tell you the news soon.He was able to flee Europe before the war broke out.2表示允許可用can或could，與may/might意義接近。could可用于現(xiàn)在時(shí)，只是語氣更

2、加委婉、客氣，回答時(shí)則一般要用can而不用could。Could I have the television on?Yes，you can./No，you cant.二、may與might1表示允許，意為“可以，許可”，用法基本上同can與could。如：May I use your bicycle?2表示可能性，意為“也許，可能”。如：According to the weather forecast, it may rain tomorrow.3may可以放在句首，表示祝愿。如：May good luck be yours!三、must與have to1must用來表示說話人的主觀看法；h

3、ave to表示客觀的需要，強(qiáng)調(diào)外界壓力，不得已而為之。如：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)My brother was ill, so I had to call the doctor in the middle of the night.我弟弟生病了，我只得半夜里把醫(yī)生請來。(客觀上需要做這件事)2表示“不必”，須用dont have to或neednt。must的否定式表示“禁止，絕對不可”。如：You dont have to tell him about it.你不必告訴他那件事。You mustnt tel

4、l him about it.你絕不能告訴他那件事。Must we do it now?我們必須現(xiàn)在做嗎？No, you neednt.不，你們不必。四、shall1用于第一、第三人稱的疑問句中，用來征求對方的意見或請求指示。如：What shall he do next?他下一步干什么呢？2用于第二、第三人稱的陳述句中，表示說話人的意愿，有“命令、警告、允諾、威脅、強(qiáng)制”等意思。如：He shall stay in bed.他必須躺在床上。You shall have it back next week.下周一定還你。He says he wont go, but I say he shal

5、l.他說他不去，但我說他必須去。五、will與would1will用于各種人稱，表示“意志、意愿”或“決心”等。如：If you will keep your watch half an hour slow, it is hardly surprising that you are late for your appointments.如果你想要讓你的表慢半個(gè)小時(shí)，你約會(huì)時(shí)遲到就不足為怪了。2will表示習(xí)慣性的動(dòng)作，有“總是，慣于”的含義。如：An Englishman will usually show you the way in the street.英國人通常是會(huì)在街上給你指路的。3

6、would可表示過去反復(fù)發(fā)生的動(dòng)作。如：On Sundays he would get up early and go fishing.星期天他總是早起去釣魚。六、should與ought to1should表示“建議”或“勸告”，有“應(yīng)該”之意。如：You should learn from each other.2ought to表示根據(jù)某種義務(wù)或必要“應(yīng)當(dāng)”做某事。如：Everyone ought to obey the traffic regulations.3should和ought to也可用來表示推測，意為“想必會(huì)”。如：When can I come for the photo

7、s? I need them tomorrow afternoon.They should be ready by 1200.七、情態(tài)動(dòng)詞表示推測1can用于肯定句中表示客觀的可能性，意為“有時(shí)會(huì)”；用于疑問句中可以表示推測，意為“可能”，有時(shí)表示一種驚訝的語氣；用于否定句中也可以表示推測，cant意為“不可能”，語氣很強(qiáng)烈。It is usually warm in my hometown in March, but it can be rather cold sometimes.我的家鄉(xiāng)在三月份通常很暖和，但有時(shí)候也會(huì)相當(dāng)冷。Mr. Bush is on time for everythi

8、ng. How can it be that he was late for the meeting?布什先生做什么事情都很準(zhǔn)時(shí)，他怎么可能開會(huì)遲到呢？Lets visit Tom together, Stephen.Theres no need to do so. He cant be at home, because I saw him board the flight to Beijing this morning.Stephen，咱們一起拜訪湯姆吧。沒必要這樣做。他一定不在家，因?yàn)榻裉煸绯课铱匆娝巧狭孙w往北京的航班。2may/might用于肯定句中可以用來表示不十分肯定的推測，意為“

9、有可能”；用于否定句中也可以表示推測，may not意為“可能不”，表示一種不太確定的語氣。The traffic is heavy these days. I might arrive a bit late, so could you save me a place?這些天交通很繁忙，我可能會(huì)來晚一點(diǎn)，請你幫我保留個(gè)位置好嗎？3must表示推測時(shí)只能用于肯定句中，意為“一定，必定”，表示十分肯定的語氣(在疑問句中或否定句中要用can/could)。Its the office! So you must know eating is not allowed here.Oh, sorry.這是辦

10、公室！所以你一定知道這里不許吃東西。噢，對不起。4should用來表示推測時(shí)意為“應(yīng)該”，即含有“按道理來說應(yīng)當(dāng)如此”的意思。There shouldnt be any difficulty about passing the road test since you have practiced a lot in the driving school.因?yàn)槟阍隈{校訓(xùn)練了這么多，通過路考應(yīng)該沒什么困難。八、“情態(tài)動(dòng)詞have done”結(jié)構(gòu)1should/ought tohave done，表示“過去本應(yīng)該做而(實(shí)際)沒有做的事情”，含有責(zé)備或遺憾的語氣，意為“本應(yīng)該”。其否定形式為“shoul

11、d not/ought not to havedone”，表示某種行為本不該發(fā)生但實(shí)際上發(fā)生了。I shouldnt have watched that movieitll give me horrible dreams.我本不應(yīng)該看那部電影它會(huì)令我做噩夢。You ought to have come to the party yesterday, but why didnt you come?昨天你本來應(yīng)該參加聚會(huì)的，可是你為什么不來？2musthave done，用于肯定句，表示“過去一定做過某事”，表示一種很有把握的推測。注意，對過去發(fā)生的情況的否定推測常用“cant/couldntha

12、ve done”表示。Ye Shiwen won two gold medals in London Olympic Games.She must have gone through tough training.葉詩文在倫敦奧運(yùn)會(huì)獲得了兩枚金牌。她肯定受到嚴(yán)格的訓(xùn)練。Do you know where David is? I couldnt find him anywhere.Well. He cant have gone farhis coats still here.你知道大衛(wèi)在哪里嗎？我到處找不到他。大衛(wèi)的上衣還在這里，因此他肯定沒走遠(yuǎn)。3neednthave done，表示“過去沒有

13、必要做某事，但實(shí)際上做了某事”。Mark neednt have hurried. After driving at top speed, he arrived half an hour early.馬克本沒必要那么匆忙。他以最快速度開車，結(jié)果早到了半個(gè)小時(shí)。4may/mighthave done，表示對過去情況的一種不太有把握的可能性的推測，表示“可能已做了某事”，否定句表示“可能還沒有”。Sorry, Im late. I might have turned off the alarm clock and gone back to sleep again.對不起，我遲到了。我可能把鬧鐘關(guān)掉

14、后又睡著了。5couldhave done表示“過去本來可以做某事，但實(shí)際上沒有做”；can/couldhave done表示“過去可能做了某件事”。I could have saved the poor rabbit, but I didnt have the right drugs with me at that moment.我本來可以拯救那只可憐的兔子的，可是我當(dāng)時(shí)沒有合適的藥品。第二部分、虛擬語氣一、虛擬語氣在虛擬條件句中的用法虛擬情況從句謂語主句謂語例句與現(xiàn)在事實(shí)相反過去式(be用were)would/should/could/might doIf he were here, he

15、 might be able to help.What would you do if you were in his place？與過去事實(shí)相反had donewould/should/could/mighthave doneIf I had started a little earlier, I would have caught the train.I could have done it better if I had been more careful.與將來事實(shí)相反過去式were to do/should dowould/should/could/mightdoIf I were

16、to do it, I would do it in a different way.I would certainly go if I had time.1.在具體運(yùn)用中，條件從句中有時(shí)可省略if而采用倒裝結(jié)構(gòu)。如：Had it not been for your help, we wouldnt have achieved so much.2介詞without/but for、連詞but、副詞otherwise常用來表示某種假設(shè)條件。如：I wouldnt have made such rapid progress without your help.3有時(shí)候從句動(dòng)作和主句動(dòng)作發(fā)生的時(shí)間不

17、一致，這時(shí)謂語動(dòng)詞的形式要根據(jù)各自的時(shí)間來調(diào)整。如：If the weather had been more favourable, the crops would be growing still better.二、“should動(dòng)詞原形”表示的虛擬語氣這一類型常見詞有“一堅(jiān)持(insist)、二命令(order, command)、三建議(advise, suggest, propose)、四要求(request, require, demand, desire)”。以上詞及其派生名詞所接的名詞性從句都使用“(should)動(dòng)詞原形”的虛擬語氣。Janes pale face sugges

18、ted that she was ill, and her mother suggested that she(should) have a medical examination.簡蒼白的臉色表明她病了，她母親建議她去檢查身體。She insisted that the man had stolen her car and that he(should) be sent to prison.她堅(jiān)持說那個(gè)男人偷了她的車，并堅(jiān)決要求他坐牢。三、特殊句式中的虛擬語氣If only/Its (high) time (that).wish/would rather/as if等固定句式要求用相應(yīng)的虛擬

19、語氣表達(dá)形式。I wish I could fly.真希望我能飛。I would rather you came tomorrow.我寧愿你明天來。If only I had taken your advice!要是聽從了你的建議該多好??！高頻考點(diǎn)一、考查情態(tài)動(dòng)詞例1（2018北京卷）In todays information age, the loss of data _ cause serious problems for a company.A. need B. should C. can D. must【答案】C【解析】考查情態(tài)動(dòng)詞。句意：在今天的信息時(shí)代，數(shù)據(jù)的丟失有時(shí)會(huì)對一個(gè)公司造

20、成嚴(yán)重的問題。數(shù)據(jù)丟失造成嚴(yán)重問題是客觀上會(huì)發(fā)生的情況，即“客觀可能性”，故該空應(yīng)用情態(tài)動(dòng)詞can。C選項(xiàng)正確。其余情態(tài)動(dòng)詞均沒有該用法。need需要；should應(yīng)該，竟然；must必須，肯定?！咀兪教骄俊緾ant you stay a little longer?Its getting late. I really _go now, My daughter is home alone.A .may B .can C . must D .dare 【答案】C【解析】句意：你不能再多待會(huì)兒嗎?很晚了，我必須得走了。我女兒一個(gè)人在家。A. may可能，可以，也許；B. can能，會(huì)；C. mus

21、t必須，必然要，必定會(huì)；D. dare敢，膽敢。結(jié)合句意，故選C。【變式探究】_ I have a word with you? It wont take long. A. CanB. MustC. ShallD. Should【答案】A【解析】本題考察的是情態(tài)動(dòng)詞基本意義辨析。Can能夠，可能；must必須，一定；非得；shall將要；should應(yīng)該；句意：我可以和你談?wù)剢?？不?huì)花很多時(shí)間的。根據(jù)句意可知本題使用can I？表示詢問對方是否允許。如：Can I use your dictionary?我可以使用你的字典嗎？故A正確。高頻考點(diǎn)二、考查情態(tài)動(dòng)詞的用法例2. （2018天津卷）

22、I cant find my purse. I_ it in the supermarket yesterday, but Im not sure.A. should leave B. must have leftC. might leave D. could have left【答案】D【解析】考查情態(tài)動(dòng)詞表推測。句意：我不能找到我的錢包了，昨天我有可能把它落到超市了，但我不確定。根據(jù)句中時(shí)間狀語yesterday可知，是對過去事情的推測，故用情態(tài)動(dòng)詞+ have done，再根據(jù)后句but Im not sure.可知，此推測為不能肯定的推測，故用情態(tài)動(dòng)詞could，表示“可能”。故選D。

23、【變式探究】（2017天津）My room is a mess, but I _clean it before I go out tonight. I can do it in the morning.A. darent B. shouldnt C. neednt D. mustnt【答案】C【解析】 句意：我的房間很亂，但是在今晚我出去之前不需要打掃，我可以明天早晨再打掃。A.不敢；B.不應(yīng)該；C不需要；D.不許。根據(jù)句意，故選C?！咀兪教骄俊縒hy didnt you tell me about your trouble last week？If you _(tell)me，I could

24、 have helped.【答案】had told【解析】句意：上個(gè)星期你為什么不告訴我你的麻煩事？如果你告訴我了，我就能幫你。根據(jù)句意和相關(guān)信息判斷，條件句表示與過去事實(shí)相反的假設(shè)，此時(shí)從句用過去完成時(shí)，主句謂語用“情態(tài)動(dòng)詞have done”形式?！咀兪教骄俊縄 _ have worried before I came to the new school, for my classmates here are very friendly to me.A. mightntB. mustntC. needntD. couldnt【答案】C【解析】句意：我來新學(xué)校之前本沒有必要擔(dān)心，因?yàn)樵谶@里我

25、的同學(xué)對我非常友好。neednt have done本沒有必要做某事，表示實(shí)際上已經(jīng)做了某事。根據(jù)句意可知選C。高頻考點(diǎn)三、考查虛擬語氣例3(2019天津卷)The workers were not better organized, otherwise they _ the task in half the time.Aaccomplished Bhad accomplishedCwould accomplish Dwould have accomplished【答案】D【解析】考查虛擬語氣。句意：工人們沒有被組織好，否則的話他們會(huì)用那一半的時(shí)間完成任務(wù)的。此處otherwise表達(dá)了一種含

26、蓄虛擬；otherwise前的內(nèi)容所述的是過去的事實(shí)，相當(dāng)于if引導(dǎo)的條件狀語從句“If the workers had been better organized”，因此后半部分應(yīng)用“主語would have done sth.”的結(jié)構(gòu)。故選D?！九e一反三】【2018江蘇】Itsstrangethathe_ havetakenthebookswithouttheownerspermission.A. would B. shouldC. could D. might【答案】B【解析】考查虛擬語氣。句意：真奇怪，他竟然沒有主人的允許就拿走了這些書。在句型”It is important/nece

27、ssary/strange/impossible/natural that.”中，其中由that引導(dǎo)的主語從句通常用“should+動(dòng)詞原形”這樣的虛擬語氣，其中的should可以省略。故選B?！咀兪教骄俊浚?017北京）If the new safety system _ to use, the accident would never have happened.A. had been put B. were put C. should be put D. would be put【答案】A【解析】句意：如果這個(gè)新的安全系統(tǒng)被投入使用過的話，這個(gè)事故就不會(huì)發(fā)生了。根據(jù)主句確定是對過去情況的

28、虛擬，所以從句謂語用had done形式，此外根據(jù)句意可知是被動(dòng)，用被動(dòng)語態(tài)，故A項(xiàng)是正確的。 【變式探究】_(have)the governments and scientists not worked together，AIDSrelated deaths would not have fallen since their highest in 2005.【答案】Had【解析】句意：如果政府和科學(xué)家不共同努力，與艾滋病相關(guān)的死亡就不會(huì)從2005年的最高點(diǎn)下降。這是一個(gè)省略了從屬連詞if的虛擬語氣句，使用了倒裝句式。根據(jù)主句的would not have fallen可知，這里是表示過去的虛

29、擬語氣，所以用had。【變式探究】Without his wartime experiences, Hemingway_ his famous novel A Farewell to Arms.A.didnt write B. hadnt written C. wouldnt write D. wouldnt have written【答案】D 【解析】句意：沒有他戰(zhàn)時(shí)的經(jīng)驗(yàn)，海明威就不可能寫出著名的小說永別了武器。根據(jù)without his wartime experience沒有戰(zhàn)時(shí)的經(jīng)歷，可知表示對于過去的否定猜測，故主句用would have done，因此選D項(xiàng)。1(2019天津卷)

30、The workers were not better organized, otherwise they _ the task in half the time.Aaccomplished Bhad accomplishedCwould accomplish Dwould have accomplished【答案】D【解析】考查虛擬語氣。句意：工人們沒有被組織好，否則的話他們會(huì)用那一半的時(shí)間完成任務(wù)的。此處otherwise表達(dá)了一種含蓄虛擬；otherwise前的內(nèi)容所述的是過去的事實(shí)，相當(dāng)于if引導(dǎo)的條件狀語從句“If the workers had been better organi

31、zed”，因此后半部分應(yīng)用“主語would have done sth.”的結(jié)構(gòu)。故選D。2(2019江蘇卷)What a pity! You missed the sightseeing, or we _ a good time together.Ahad Bwill haveCwould have had Dhad had【答案】C【解析】考查虛擬語氣。句意：多么遺憾！你錯(cuò)過了這次游覽。否則，我們就可以一起度過一段愉快的時(shí)光。根據(jù)關(guān)鍵詞or可知，這里表示與過去的事實(shí)相反，謂語動(dòng)詞應(yīng)用would/could/should/mighthave done。1.【2018江蘇】 There is

32、a good social life in the village, and I wish I _ a second chance to become more involved.A. had B. will haveC. would have had D. have had【答案】A【解析】考查虛擬語氣。句意：在這個(gè)村里有很好的社交生活，并且我希望我再有機(jī)會(huì)去更多的參與。本題考查wish引導(dǎo)的賓語從句，表示與現(xiàn)在事實(shí)相反的愿望，所以從句用一般過去時(shí)。故選A。2.【2018江蘇】Itsstrangethathe_ havetakenthebookswithouttheownerspermiss

33、ion.A. would B. shouldC. could D. might【答案】B【解析】考查虛擬語氣。句意：真奇怪，他竟然沒有主人的允許就拿走了這些書。在句型”It is important/necessary/strange/impossible/natural that.”中，其中由that引導(dǎo)的主語從句通常用“should+動(dòng)詞原形”這樣的虛擬語氣，其中的should可以省略。故選B。3.（2018天津卷） I cant find my purse. I_ it in the supermarket yesterday, but Im not sure.A. should lea

34、ve B. must have leftC. might leave D. could have left【答案】D【解析】考查情態(tài)動(dòng)詞表推測。句意：我不能找到我的錢包了，昨天我有可能把它落到超市了，但我不確定。根據(jù)句中時(shí)間狀語yesterday可知，是對過去事情的推測，故用情態(tài)動(dòng)詞+ have done，再根據(jù)后句but Im not sure.可知，此推測為不能肯定的推測，故用情態(tài)動(dòng)詞could，表示“可能”。故選D。4.（2018北京卷）In todays information age, the loss of data _ cause serious problems for a c

35、ompany.A. need B. should C. can D. must【答案】C【解析】考查情態(tài)動(dòng)詞。句意：在今天的信息時(shí)代，數(shù)據(jù)的丟失有時(shí)會(huì)對一個(gè)公司造成嚴(yán)重的問題。數(shù)據(jù)丟失造成嚴(yán)重問題是客觀上會(huì)發(fā)生的情況，即“客觀可能性”，故該空應(yīng)用情態(tài)動(dòng)詞can。C選項(xiàng)正確。其余情態(tài)動(dòng)詞均沒有該用法。need需要；should應(yīng)該，竟然；must必須，肯定。5.（2018北京卷）They might have found a better hotel if they _ a few more kilometers.A. drove B. would drive C. were to drive

36、D. had driven【答案】D【解析】考查虛擬語氣。句意：如果他們多開幾公里的話，他們也許會(huì)找到一個(gè)更好的旅館。由“they might have found a better hotel”可知，該句是表示對過去的虛擬。if _ a few more kilometers是條件句部分，表示對過去的虛擬，條件句部分要用過去完成時(shí)態(tài)，故D選項(xiàng)正確。1（2017北京）Samuel, the tallest boy in our class, _ easily reach the books on the top shelf.A. must B. should C. can D. need【答案

37、】C【解析】A. must 必須 B. should 應(yīng)該 C. can 能 D. need 需要。句意:Samuel，我班最高的男生，能很輕松地夠著書架頂上的書，此處需要一個(gè)表示能力的詞，故用can，答案為C。2（2017天津）My room is a mess, but I _clean it before I go out tonight. I can do it in the morning.A. darent B. shouldnt C. neednt D. mustnt【答案】C【解析】 句意：我的房間很亂，但是在今晚我出去之前不需要打掃，我可以明天早晨再打掃。A.不敢；B.不應(yīng)該

38、；C不需要；D.不許。根據(jù)句意，故選C。3（2017江蘇） _ not for the support of the teachers, the student could not overcome her difficulty. A. It were B. Were it C. It was D. Was it【答案】B【解析】考查虛擬語氣和倒裝。虛擬語氣中，be動(dòng)詞統(tǒng)一用were；虛擬語氣的省略形式主要是把if省略，同時(shí)把were/should/had提前，即Were /Should/ Had I.，故選B。句意：要不是老師們的支持，該生是無法克服她自己的困難的。4 (2017江蘇卷) _ not for the support of the teachers, the student could not overcome her di