高三英语语法总复习动词不定式

动词不定式,一、不定式结构作主语,Toseeonetimeisbetterthantohearahundredtimes.Toperseveremeansvictory!注：在很多情况下，特别是在口语中，常采用先行it代替主语，而把不定式后置：Itsagreatpleasuretobehere.Itisnotaneasythingtomasteralanguage.注：这种后置不定式的结构也适用于某些谓语动词不是系动词的句子，如：Ittookusfivehourstogetthere.Itmadeusveryangrytohearhimtalklikethat.,注：不定式结构的逻辑主语通常可在特定的上下文或情景中看出，也可以由“for+名词词组”来表示，如：Itisnothardforonetodoabitofgood.Itwasdifficultformetodothework.注：某些形容词在上述结构中作表语时，常在不定式之前加上“of+名词词组”来说明不定式所指的是谁的情况，如：Itskindofyoutothinksomuchofus.Itsveryniceofyoutobesoconsiderate.Itsunwiseofthemtoturndowntheproposal.Itwascarelessofhertomakesuchamistake.,二、不定式结构作表语,1主语和表语都是不定式（其含义往往一是条件，一是结果），如：Tobekindtotheenemyistobecrueltothepeople.Todothatwouldbetocutthefoottofittheshoe.2主语是以aim,duty,hope,idea,intention,mistake,plan,proposal,job,suggestion等为中心词的名词词组，或以what引导的名词性从句表示，后面的不定式说明其内容，如：Myideaistoclimbthemountainfromthenorth.Yourmistakewasnottowritethatletter.Mysuggestionistostartworkatonce.WhatIwouldsuggestistostartworkatonce.注：在某些句型中，当主语部分有动作动词do时，作表语的不定式可以省略符号“to”，如：Allwehavetodoispushthebutton.TheonlythingIcandonowisgoonbymyself.AllIcoulddowassendhimatelegram.,三、不定式结构作动词宾语,1“动词+带to的不定式结构”。这类动词常见的有：afford,agree,arrange,ask,choose,decide,demand,desire,expect,hope,learn,manage,offer,pretend,promise,refuse,want,wish,like,hate,prefer,continue,try,start,forget,mean,intend,begin,等，例如：Ivearrangedtomeethimattenoclock.Ididntexpecttofindyouhere.2“动词+疑问词+带to的不定式结构”。（这种不定式结构接近一个名词从句）。这类动词常见的有：tell,advise,show,teach,findout,decide,discuss,learn,forget,inquire,know,explain,remember,see,understand,wonder等。疑问词（也称连接代/副词）有：what,where,who(m),when,how,whether,which（why除外），如：Idontknowwhattodo/wheretogo/who(m)toask/whentostop/howtogetthere.Ihaventdecidedwhethertosellitornot.Wemustfindoutwhattodonext/wheretoputit.,注：如果作宾语的不定式结构有自己的补语，则应使用先行it，把不定式后置，例如：Ifinditdifficulttounderstandhim.Wethoughtitwrongnottohelpher.Theyfounditimpossibletogeteverythingreadyintime.注：不定式结构一般不可作介词宾语,只有在个别场合,即在含有否定意义的带有介词except或but(=except)的结构中才能这样用，例如：Heseldomcomesexcepttolookatmypictures.Thechilddidnothingexceptweep.Shecandoanythingbutsing.Hewilldoanythingforyouexceptlendyoumoney.Theycoulddonothingbutwaitforthedoctorstoarrive.注意不定式符号的省略问题！,四、不定式结构作定语,1不定式作定语通常只能放在被修饰的名词之后，如：Itstimetogotobed.Heisnotamantobowbeforedifficulties.Haveyouanythingtodeclare?Sheusuallyhasalotofmeetingstoattendintheevening.Iwanttogetsomethingtoreadduringthevocation.2能带不定式结构作宾语的动词，转化成名词时往往也能带不定式结构作定语，如：Idontwishtoquarrelwithyou.Ihavenowishtoquarrelwithyou.Theywillattempttocrosstherivertonight.Theywillmakeanotherattempttocrosstherivertonight.Shepromisednottodothatagain.Shemadeapromisenottodothatagain.,3某些能带不定式结构作状语的形容词，转化成名词时，也能带不定式结构作定语，如：Hewasobviouslyanxioustogo.Hisanxietytogowasobvious.4不定式结构与所修饰的名词，有时意义上有着主谓关系或动宾关系，如：Hehasalargefamilytosupport(=thathemustsupport).注：处于动宾关系的情况下，如果不定式是不及物动词，它后面应加上必要的介词，如：Shehasalotofthingstoattendto.Thenursehasfivechildrentolookafter.Letsfirstfindaroomtoputthethingsin.5有时为了明确不定式结构的逻辑关系，可以在不定式之前加上for+名词词组，如：Heresabookforyoutoread.Hegaveordersforthevisitorstobeshownin.,五、不定式结构作状语,不定式结构可以作状语，修饰动词、形容词、副词等，表示目的、原因、结果、条件等。,1表示目的：Theyranovertowelcomethedelegates.Heboughtabicycletogototownmorequickly.Hewenthometoseehismother.注：不定式结构表示目的时，通常句子的主语就是它的逻辑主语(参见以上三句)，但也有例外的情况，例如：Istoppedforhimtospeaktome.Heopenedthedoorforthechildrentocomein.Hebroughtaportertocarrytheboxes/bags.Theysentamantomendthewindow.Hestooduptobeseenbetter.,注：为了强调表示目的的不定式结构，特别是在不定式结构前有否定词not时，通常可以在不定式符号to之前加上inorder或soas，如：HecamehereinordertoseeCharlie.Heshoutedandwavedsoastobenoticed.Hewentearlyinordernottomissthetrain.Iturnedtheradiodownsoasnottodisturbhim.注：表示目的的不定式可以置于句首，这也是区别于其他功能的标志之一。但是，置于句首表示目的的不定式之前可以加上inorder，但却不可以加上soas，如：Todrawmapsproperly,youneedaspecialpen.(Inordertodrawmapsproperly,youneedaspecialpen.)Togetthebestresults,usecleanwater.,2.表示结果：WhathaveIsaidtomakeyousoangry?Hecameroundtofindhimselfinhospital.不定式结构表示结果更常见于下列句型：soastoWouldyoubesokindastolendmeyourbicycle/tellmethetime?such()astoImnotsuchafoolastobelievethat.enoughtoTheboyisoldenoughtogotoschool.tootoHiseyesightistoopoortoreadsuchsmallletters.注意：下列句子中的不表示结果，也无否定含义：Imonlytoogladtogo.(=Imverygladtogo.)Ishallbeonlytoopleasedtogethome.(=Ishallbeverypleasedtogethome.)onlytoo(adv.)极;非常;太;很,有时，不定式结构还能表示一个随后发生的动作，相当于一个并列限定动词词组，这种不定式结构也表示结果，如：Shewokeearlytofinditwasraining.Hegothometolearnthathisfatherwasill.这种表示结果的不定式结构具有下列几个特点：不定式所表示的动作是随后发生的，相当于一个限定动词词组，如：Hearrivedlatetofindtheothershadgonehome.Hearrivedlateandfoundtheothershadgonehome.不定式根据是否需要停顿而决定与主句是否用逗号隔开。Helefthisnativecountry(,)nevertoreturn.Hereturnedhome(,)tofindhisfatherlyingsickinbed.不定式所表示的结果往往含有“令人意想不到”的意味，其中以“使人不愉快的结果”较为常见。（有时也可以表示令人愉快、惊喜的结果），如：HewenthometofindhisoldfriendGeorgewaitingforhim.,不定式之前有时可以加上only或butonly，以加强语气，如：Hegottothestationonlytobetoldthetrainhadgone.Theyliftedarockonlytodropitontheirownfeet.注：不定式结构表示结果或表示目的，往往形式相似，这时，须根据词汇意义认真加以区别，试比较：Hearrivedlatetofindtheothershadgonehome.(=Hearrivedlateandfoundtheothershadgonehome.)HearrivedlatetoavoidmeetingRobert.(=HearrivedlateinordertoavoidmeetingRobert.)Hegottothestationonlytobetoldthetrainhadgone.Hewenttothestationtoinquireaboutthetimesoftrains.(=Hewenttothestationinordertoinquireaboutthetimesoftrains.),3.表示原因：（不定式所表示的动作先于谓语动词的动作）Shewepttohearthenews.Ipretendtobehappytoknowhim.Helaughedtoseesuchfun.Sheseemedsurprisedtomeetus.,六、不定式结构作宾语补足语,Dontforceyourselftowritewhenyouhavenothingtosay.Hebelievedtheearthtobeaglobe.Didyouseeayoungmanenterthehouse?1只能用不定式结构作宾语补足语的动词：表示“希望”“愿望”等心理状态的动词，如：wish,desire,expect,love,prefer,encourage,trust等。Whatdoyoudesiremetodo?Thedirectorpreferredhertoacttheoldlady.含有“让”“允许”“促使”“致使”等祈使意义的动词，如：let,allow,permit,decide,mean,lead,bring,put,hurry,cause,等。Wemustntletthishappenagain.Hisfatherputhimtomindthesheep.带有“请求”“恳求”等感情色彩的动词，如：ask,desire,invite,beg,request,worry等。Hebeggedmenottotellhisfatheraboutit.ShewasalwaysworryingherfathertotakehertoParis.,含有“建议”“劝告”等意义的动词，如：advise,persuade,callon,urge等。Heurgedustoacceptthecompromise.Thedentistadvisedmetohavethebadtoothpulledout.含有“命令”“强迫”“禁止”等意义的动词，如：order,command,require,charge,tell,make,oblige,force,drive,forbid,warn等。Herequiredustokeepitasecret.Thedoctororderedhimtostayinbedforafewdays.Iwarnyounottodothatagain.其他还有：help,teach,show,assist,report,bear,waitfor,train,dependon等。Hepromisedtoteachmetoswim.Weshouldtrainthemtomakeuseofreferencebooks.Wearewaitingforthetraintostop.,2既能用不定式结构又能用现在分词作宾语补足语的动词：see,watch,notice,lookat,hear,listento,observe,feel,have;imagine,find,discover,like,want,understand,hate,bring,get,leave,setDidyouseeanyoneenterthehouse?Dontimagineyourselftobealwayscorrect.Wefindhimtobedishonest.Hesettheboystocarrywater.Illleavehimtosolvetheproblemforhimself.,注：有些动词用不定式与用现在分词作宾语补足语，所表达的意义是有差别的。一般说来，用不定式表示一次性动作或动作的完成（即全过程）；而用现在分词则表示动作正在进行，即：谓语动词所表示的动作发生时，现在分词所表示的动作正在进行，如：Didyouseeanyoneenterthehouse?Hesawhisfathertalkingwithhisteacher.Ionceheardhimsingthissong.SheheardMr.Whitesinginginthenextroom.,注：使用不定式作宾语补足语时，在有些动词后面，不定式符号to应当省略。下列动词用不定式作宾语补足语时，必须省去不定式符号to：let,make,have,see,watch,notice,lookat,observe,hear,listentoHeobservedsomeoneopenthedoor.Iwatchedthemgetintothecar.Didyounoticehimleavetheroom?feel一词在使用todo型不定式作宾语补足语时，不带to；在使用tobe型不定式时，要带to，如：Hefeltthemtoberight.Didyoufeeltheearthshake?help一词在使用不定式作宾语补足语时，可以带to，也可以不带to，如：Doyouoftenhelpyourmother(to)dothehousework?使用不定式作宾语补足语的句子，改为被动结构以后，宾语补足语就成了主语补足语，这时，“to”不可以省略，如：Thebossmadethemworkfrommorningtillnight.Theyweremadetoworkfrommorningtillnight.,不定式的一般式所表示的动作，通常与主要谓语所表示的动作（或状态）同时（或几乎同时）发生，或者是在它之后发生,例如：Whoheardhimsaythat?Theyinvitedustogotherethissummer.如果不定式所表示的动作在谓语所表示的动作之前发生，这个不定式就要用完成式，如：Imgladtohaveseenyourmother.(cf.Imgladtoseeyou.),七、不定式的完成式有下列用法,1构成复合谓语，如：Heissaidtohavewrittenanewbookaboutworkers.(Itissaidthathehaswrittenanewbookaboutworkers.)Theenemywasreportedtohavesurrendered.(Itwasreportedthattheenemyhadsurrendered.)Sheseemedtohaveheardaboutitalready.(Itseemedthatshehadalreadyheardaboutit.),2在某些作表语用的形容词后作状语，如：Youareluckytohavegotticketstotheconcert.(=Youareluckythatyouhavegotticketstotheconcert.)Imsorrytohavegivenyousomuchtrouble.(=ImsorryIhavegivenyousomuchtrouble.)Shewasverygladtohavedonesomethingforthepeople.3在某些动词后作宾语，如：Hepretendednottohaveseenme.Imeanttohavetoldyouaboutit,butIforgottodoso.4有时还可以作主语、定语或构成复合宾语，如：Itwasagreatsatisfactiontohaverevisitedournativevillage.（主语）Soyouaretheonetohavecleanedalltheserooms.（定语）Theythoughtitapitynottohaveinvitedher.（复合宾语）Shefeltitanhonourtohavetakenpartinthework.（复合宾语）,如果主要谓语所表示的动作（或情况）发生时，不定式所表示的动作正在进行，这时，不定式就要用进行式。,八、不定式的进行式主要有下列几种用法,1构成复合谓语，如：Theyaresaidtobebuildinganotherbridgeacrosstheriver.Theyseemtobegettingalongquitewell.Ihappenedtobegoingthatwaytoo.2在某些动词后构成复合宾语，如：Wedidntexpectyoutobewaitingforushere.3在某些动词后作宾语，如：Hepretendedtobe