2013年高考第二轮复习英语广东版语法热点突破第八讲 情态动词和虚拟语气一、情态动词1．情态动词具有以下三个特点：（1）后面接动词原形。（2）没有人称和数的变化。（3）变为疑问句或否定句时不需要加助动词，而是将情态动词移至主语前变为疑问句；在情态动词后加not，构成否定句。2．“情态动词＋havedone”表示推测、必要性情态动词＋have＋过去分词用法musthavedone表示对过去已经发生的行为进行推测，意为“想必/准是/一定做了某事”can/couldhavedone表示对过去发生的行为的怀疑和不肯定，通常用在否定句和疑问句中couldhavedone可用于肯定句中，表示“可能已经……”；此外，还可表示过去没有实现的可能性，意为“本来可以……”may/might（not）havedone表示对过去已发生行为的推测，用于肯定句中，表示“也许已经……”；在否定句中表示“可能不”，用might则表示语气更加不肯定should/ought（not）tohavedone用于肯定句中，表示“本该做某事，而实际上未做”；用于否定句中，则表示“不该做的事反而做了”needn'thavedone表示“本来没必要做某事”，指做了本来不必去做的事Theymusthave_fallen（fall）asleep.IsawMr.Wangjustnow.Hecouldn'thave_gone（go）toBeijing.Youcouldhavedonebetter，butyouweretoocareless.Youshouldhavecometothemeetingearlier.3．表示能力，can与beableto一般可互换，但beableto可用于将来时和完成时等时态；在表示过去具体某次能够成功做成某事时，只能用was/wereableto。4．表示请求许可，可说May/Might/Can/CouldI...？但表示给予许可时，不能用might/could，即不说youmight/could。5．must与haveto的区别：must强调主观认为“必须”做某事，而haveto强调客观上要求“不得不”做某事；haveto有过去式（hadto）和将来时（willhaveto）等时态；mustn't意为“不准”，don'thaveto＝needn't，意为“不必”。另外，must还可表示“硬要，偏要”。6．should可表示“万一，竟然”。7．表示“应该，应当”，should和oughtto可互换，只是oughtto的语气稍重；should强调主观看法，而oughtto强调客观要求。8．shall在陈述句中表示说话者给对方的承诺、决心、警告、威胁等；也可在法令、条约、规章中表示强制，意为“必须，应该”。还可以用于ShallI/he...（要不要我/他……？……好吗？）。9．might/mayaswell“不妨，还是……为好”；hadbetterdosth.“最好做某事”；wouldratherdosth.“宁愿做某事”。10．“cannothelpbut＋动词原形”表示“不得不，只好”。Icannothelpbutgo.11．cannot/cannever...enough/too...表示“再……也不为过”。Youcannotbecarefulenoughtocrosstheroad.-4-\n二、虚拟语气类别用法例句if引导的条件从句与现在事实相反从句谓语动词：过去式（be用were）主句谓语动词：should/would/could/might＋动词原形Ifhewerehere，hewouldhelpus.与过去事实相反从句谓语动词：had＋过去分词主句谓语动词：should/would/could/might＋have＋过去分词IfIhadbeenfree，Iwouldhavevisitedyou.与将来事实相反从句谓语动词：过去式/should＋动词原形/were＋不定式主句谓语动词：should/would/could/might＋动词原形Ifitshouldraintomorrow，wewouldnotgocamping.其他状语从句asif引导的状语从句中谓语动词用过去式（与现在事实不符）或过去完成式（与过去事实不符）Theyoungmanwithlonghairwalksasifhewereagirl.inorderthat/sothat引导的状语从句中谓语动词用can/could/may/might/would等＋动词原形Turnonthelightsothatwecanseeitclearly.宾语从句demand，suggest，order，insist后接的从句中谓语动词用“should＋动词原形”Hesuggestedthatwe（should）notchangeourmind.wish后的从句中谓语动词分别用过去式，过去完成式和should/would＋动词原形，表示与现在、过去和将来情况相反IwishIcouldbeapopsinger.主语从句在Itisnecessary/important/strangethat...，Itissuggested/demanded/ordered/requestedthat...等从句中，谓语动词用“should＋动词原形”Itisstrangethatsuchapersonshouldbeourfriends.其他句型中Itis（high）timethat...句型中that从句谓语动词用过去式或should＋动词原形It'shightimethatweleft.wouldrather所接的从句中that从句谓语动词用过去式或过去完成式Iwouldratheryoustayedathomenow.ifonly句型中动词常用过去式或过去完成式，表示强烈的愿望Ifonlyourdreamhadcometrue！即时训练Ⅰ．在下列各句中填入适当的情态动词1．（2011·江西高考）It______（not）bethepostmanatthedoor.It'sonlysixo'clock.2．（2011·辽宁高考）Ifyou______go，atleastwaituntilthestormisover.3．（2011·新课标全国高考）They______havearrivedatlunchtimebuttheirflightwasdelayed.4．（2011·重庆高考）—Whydidn'tyoucometoSimon'spartylastnight?—Iwantedto，butmymomsimply______notletmeoutsolateatnight.5．（2011·浙江高考）—How'syournewbabysitter?—We______（not）askforabetterone.Allourkidslovehersomuch.6．（2011·陕西高考）I______（not）gothroughthatbitterperiodwithoutyourgeneroushelp.7．（2011·陕西高考）—Willyoureadmeastory，Mummy?—OK.You______haveoneifyougotobedassoonaspossible.8．（2011·上海高考）I______（not）worryaboutmyweekend—Ialwayshavemyplansreadybeforeitcomes.-4-\n9．There______（not）beanydifficultyaboutpassingtheroadtestsinceyouhavepracticedalotinthedrivingschool.10．TheWorldWideWebissometimesjokinglycalledtheWorldWideWaitbecauseit______beveryslow.11．I______notstayforlunch.Mybrotheriscomingtoseeme.12．IfI______plantodoanythingIwantedto，I'dliketogotoTibetandtravelthroughasmuchofitaspossible.13．Tom，you______notleaveallyourclothesonthefloorlikethis!14．（2011·北京高考）—Idon'treallylikeJames.Whydidyouinvitehim?—Don'tworry.He______notcome.Hesaidhewasn'tcertainwhathisplanswere.15．（2011·湖南高考）—Noone______becomparedwithYaoMinginplayingbasketball.—Oh，youarereallyhisbigfan.Ⅱ．用所给动词的适当形式填空1．（2011·北京高考）—Wherearethechildren？Thedinner'sgoingtobecompletelyruined.—Iwishthey______（notbe）alwayslate.2．（2011·北京高考）MaybeifI______（study）science，andnotliteraturethen，Iwouldbeabletogiveyoumorehelp.3．（2011·江西高考）We______（put）John'snameontheracelistyesterdaybutforhisrecentinjury.4．Ifshe______（come）heretomorrow，she______（tell）methat.WeknowshewillflytoBeijingtomorrow.5．IfI______（see）himtomorrow，Iwillgiveittohim.6．IwishI______（have）aroomofmyownwhenIwasaboy.7．IwishI______（go）touniversitynextyear，sonowImuststudymuchharder.8．Isuggestedthathe______（go）thereatonce.9．Heinsistedhe______（send）tothecity.10．Hisexpressionsuggestedthathe______（pass）thetest.11．Iwasillyesterday.Otherwise，I______（take）partinthesportsmeeting.12．IfonlyI______（see）thefilm.13．You______（come）totheconferenceyesterday.Whatwasthereasonforyourabsence?14．I______（work）outtheproblem，butIwastoonervous.15．Theyinsistedthattheboy______（go）withthem.-4-\n参考答案第八讲 情态动词和虚拟语气Ⅰ．1．can't 2．must 3．should 4．would 5．couldn't 6．couldn't7．shall 8．needn't 9．shouldn't 10．can 11．can 12．could 13．must14．might 15．canⅡ．1．weren't 2．hadstudied 3．wouldhaveput 4．came/weretocome/shouldcome；mighttell 5．see 6．hadhad 7．willgo 8．（should）go 9．（should）besent 10．hadpassed 11．wouldhavetaken 12．hadseen 13．shouldhavecome 14．couldhaveworked 15．（should）go-4-
