高中英语语法情态动词复习课件 29页

情态动词一、情态动词的基本用法：1.can/could表示能力;Eg.Hecanspeakthreelanguages.Shecouldswimattheageof5.表示客观的可能性；Eg.Accidentscanhappentoanydrunkendriver.Swimminginthelakecanbedangerous.\n表示请求和允许；Eg.CanIhavealoolkatyournewwatch?Yes,ofcourseyoucan.表示请求时，口语中常用could代替can使语气婉转，但回答时仍用can；Eg.CouldyoupleasehelpmelearnEnglsih?Yes,Ican.表示惊讶、怀疑、不相信的态度（主要用于否定句、疑问句）；Eg.Howcanyoubelievesuchaliarashim?Thatcan’tbetrue.\n2.may/might表示允许、许可；（否定回答用mustn’t,表示“禁止”）Eg.MayIlistentomusicwhiledoingmyhomework?No,youmustn’t.表示请求许可时，might比may的语气更委婉些；Eg.May/MightItroubleyoutopassmethebook?\n表示可能性的推测，might比may的语气显得更加不肯定；Eg.Tommaygotothecinemawithusthisevening.Tommightgotothecinemawithusthisevening.may用于祈使句表示祝愿；Eg.Mayyouhaveahappylife.Mayyousucceed.\n3.will/would表示意志或意愿；（will表示现在，would表示过去）Eg.Iwilltellyouaboutit.Hetoldmethathewouldhelpme.用于第二人称时表示请求、建议等，用would比will委婉、客气；Eg.Willyougetmeadictionary?Wouldyoucomethisway,please?\n表示习惯性的动作，意为“惯于”；（will表示现在，would表示过去）Eg.Thatoldwomanisstrange.Shewilllsitforhourswithoutsayinganything.Whenhewasyoung.Hewouldpractiseplayingthepianoforhoursaday.表示预料或猜想;Eg.Itwillbetenwhenwegetthere.表示规律性的“注定会”用will；Eg.Peoplewilldiewithoutwater.Shewillbetwelvenextyear.\n4.need表示“需要、必要”，作情态动词，仅用于否定句和疑问句。Eg.NeedItellhimeverything?Yes,youmust./No,youneedn’t.用作实义动词时，其变化与一般动词相同：Eg.IneedtogotoNanjingtoattendameetingthisweekend.\n5.dare表示“敢、敢于”；作情态动词，主要用于疑问句、否定句和条件句中。Eg.Darehetellthemwhatheknows?Theydarenotgooutaloneatnight.用于实义动词，在否定句中可接带to或不带to的不定式。Eg.Hedaresnot(to)tellthemanagerthetruth.\n6.oughtto表示“应该”同should；Eg.Humanoughttostoppollutingthenature.Yououghtnottogetinvolvedinthematter.表示推测，意为“想必”；Eg.TheyoughttogettoBeijingbynow.\n7.must表示“必须、应该”语气比should,oughtto强烈，否定形式mustn’t表示“不准、不应该、禁止”等；Eg.Driversmustn’tdriveafterdrinking.Youmustbecarefulwhencrossingthestreet.在回答带有must的问句时，否定回答常用needn’t或don’thaveto，表示“不必”而不用“mustn’t”；Eg.MustIfinishmyhomeworkbeforeeight?No,youneedn’t./No,youdon’thaveto.\n表示很有把握的推测，意为“一定、准时”，用于肯定句；Eg.Youmustbeill.Icanseeitfromyourface.Theymustbeplayingbasketballnow.表示偏执、固执；Eg.Whymustyoualwaysinterruptme?Mustyouplaythepianonow?\n8.shall用于第一、第三人称疑问句中，表示说话人征求对方的意见和向对方请示;Eg.Shallwehaveapartythisweekend?ShallTomgotothecinemawithusthisevening?用于第二、第三人称陈述句中，表示说话人给对方的命令、警告、允许或威胁；Eg.Youshallgetateachertohelpyourson.Yourpicturesshallbereadythisafternoon.\n9.should用于表示劝告或建议，作“应该”讲；Eg.IthinkweshouldworkhardatEnglish.Youshouldtellhimthetruth.用于表示推测，译作“可能，准是”；Eg.ItshouldbeMarywhohastakenallthebooks.Theyshouldgettherenow.用于第一人称时可表示说话人的一种谦逊、客气、委婉的语气；Eg.Youaremistaken,Ishouldsay.\n“Why/How+should…”结构表示说话人对某事不能理解，感到意外、惊讶等，意为“竟会”；Eg.Whyshouldyoubesoearlytoday?Howshouldyoubesoangryathiswords?\n二、常见的用法比较：1.can’t意为“不可能，一定不”，而maynot意为“可能不、或许不”，前者语气更强；Eg.Theycan’tbeathomenow.他们现在不可能在家。Theymaynotathomenow.他们现在可能不在家。\n2.must表示说话认得主观看法，而haveto表示客观的需要；mustn’t表示“决不能”，而don’thaveto意为“不必”；Eg.Youmustbesleepynow.Ihavetoleavenow,it’stoolate.MayIhavealookatyourwatch？No,youmustn’t.Youdon’thavetogetupsoearlyonweekends.\n3.would可表示过去反复发生的动作或某种倾向，后面要接表示动作的动词，不能接表示认识或状态的词。usedto表示过去习惯的动作或状态，强调现在已经不存在。Eg.HewouldoftencometoseemewhenIwaslivinginthecountry.Heusedtoswimintheriverwhenhewasyoung.Thereusedtobealake.\n4.haveto和havegotto都可表示“不得不”，注意以下几点：表示习惯性动作，尤其句中含有always,often,sometimes等时，用haveto:Eg.IalwayshavetogetupearlyonSundays.Shesometimeshastowork12hoursaday.haveto之前可加情态动词和助动词，但havegotto前不能：Eg.IshallhavetohelphimasmuchasIcan.\nhaveto的否定式为dong’thaveto,而havegotto的否定式为haven’tgotto;前者的疑问句式借助于do,后者直接将have提前：Eg.Youdon'thavetotellhimallaboutit.Doyouhavetogotothecinemawithherthisevening?I’mgladIhaven’tgottoworktoday.Haveyougottofinishyourhomeworktoday?\n5.can与beableto的用法比较：beableto有更多的时态：Eg.Willyoubeabletohelpustomorrow?I’msorrythatIhaven'tbeenabletoansweryourletterintime.在过去时态中，could仅指具备某种能力，但实施的结果不明确，而was/wereableto不经说明有某种能力，而且成功地做到了。Eg.HewasabletofleeEuropebeforethewarbrokeout.在否定句或与感官动词连用时，could与was/wereableto可以通用。Eg.Hehurthislegandcouldn’t/wasn’tabletoplayfootball.\n三、情态动词加动词的时态：1.情态动词+be+n.adj.介词短语V-ingEg.Thatmanmustbeathief.Tommaybeathome.MarymustbefromAmerican.Theycan’tbelearningEnglishnow.Mikemustbeplayingbasketballnow.\n2.情态动词+have+P.P.+O.S+shouldhave+P.P.+O.本来应该做某事但实际上没有做Eg.Ishouldhavetoldyouthenewsearlier.Youshouldhavehelpedhim.S+shouldn’thave+P.P.+O.本来不应该做某事但实际上做了Eg.Youshouldn’thavetoldhimmysecret.Youshouln’thavegivenyoursonsomuchpocketmoney.\nS+oughttohave+P.P.+O.本来应该做某事但实际上没有做Eg.Tomoughttohavereviewedhislessonslastnight.YououghttohavespentmoretimeinlearningEnglishwhenyouwereyoung.S+oughtnottohave+P.P.+O.本来不应该做某事但实际上做了Eg.Yououghtnottohavedrivensocarelessly.Theyoughtnottohavebeenallowedtoswiminthelake.\nS+musthave+P.P.+O.过去一定发生过某事/主语过去一定做过某事Eg.Itmusthaverainedlastnightforthegroundiswet.HemusthavelivedinAmericaformanyyearsforhespeaksperfectEnglish.S+couldn’thave+P.P.+O.过去不可能发生过某事/主语过去不可能做过某事Eg.Youcouldn’thaveseenTomyesterdayforhewenttoEnglandlastweek.Itcouldn’thaverainedlastnightforthegroundisdry.\nS+couldhave+P.P.+O.本来能够做某事但实际上没有做/原本很可能发生某事Eg.Youcouldhaveturnedtomeforhelp.Youshouldhavebeenmorecareful.Youcouldhavebeenkilledbythecarjustnow.S+mighthave+P.P.+O.主语可能已经做了某事/某事可能已经发生（可能性较小）Eg.Thefillmmighthavebegun.Theymighthaveleft.\nS+needn’thave+P.P.+O.主语本不需要做某事但实际上做了Eg.Youneedn’thavewashedmyshoes.Theyarestillclean.Tomneedn’thavecomeyesterday.四、情态动词用法特例：canbut“只好、至多不过”：Eg.Wecanbutdoourbest.我们只好尽力而为。Withnokeyonhimhecanbutwaitoutsidethedoor.\ncan’thelpbutdosth,can’thelpdoingsth“不得不、不能避免、不禁”Eg.Thegirlcouldn’thelpbutliveonherself.Therefugeescouldn’thelpcryingwhentheyreturnedtotheirmotherland.cannot…too…=cannever…too…“无论怎样……都不过分、越……越……”：Eg.Wecan’tthankyoutoomuchforwhatyouhavedoneforus.Youcanneverdotheworktoowell.Youcanneverbetoocarefulwhencrossingthestreet.\nmay/might…but…“我承认……是事实，但是……”：Eg.Hemayhavelivedhereforyears,buthehasveryfewfriendshere.TommayhavellearntChineseforalongtime,buthestillcannotcommunicateinChinesefreely.may/mightaswell“还是……的好”：Eg.It’stoolate.Youmightaswellnotgo.Imayaswellbookataleinadvance.\nTHANKS!LIVEWITHPASSION!ENJOYYOURSTUDY!