动词不定式用法

动词不定式用法小结•动词不定式是一种非谓语动词形式，其结构为“to＋动词原形”，其中to不是介词，而是动词不定式的符号，称为小品词，动词不定式没有人称和数的变化。动词不定式和其后面的名词等构成不定式短语，在句子中可以用作主语、表语、宾语、补足语、定语、状语等。一.作主语：Tolookaftermypetsproperlytakesalotoftime.•Tobeadoctorishard.•TolearnEnglishwellisnoteasy.动词不定式短语作主语时，为了避免句子的头重脚轻，可以用“it”作形式主语，而把真正的主语－动词不定式短语放在句子的后部。例如上面的句子可以表示为：Itishardtobeadoctor.ItisnoteasytolearnEnglishwell.再如：It’simportanttoplanttreesinspring.如果表示动词不定式的动作执行者，可以在不定式前面加一个由介词for引导的短语，称为不定式的复合结构。例：•It’sgoodforustoreadEnglishaloudinthemorning.•ItisimportantforstudentstouseEnglisheveryday.MyambitionistoworkforfirmthatdevelopscomputersoftwarewhenIgrowup.二.作表语：动词不定式（短语）作表语常用于系词be的后面。例：Hisworkistodriveacar.Myjobistofeedanimals.Herambitionistobeadoctor.Hehopestobecomeateacher.三.作宾语动词不定式（短语）可以放在一些动词后面用作宾语，能以动词不定式作宾语的动词有：begin,start,want,forget,remember,show,learn,like,hate,love,ask等。例：•Iwanttotellyouastory.•Theybegintoworkateighteverymorning.•Don’tforgettolockthedoor.•Wouldyouliketogoandhaveapicnicwithustomorrow?注意：（1）如果and连接两个动词不定式，第二个动词不定式一般省“to”例：Hewantstogoandhaveaswimwithus.（2）若作宾语的动词不定式（短语）很长，可用it作形式宾语。IfinditinterestingtolearnEnglishwithyou.Hefoundithardtocatchupwithothers.Theteacheradvisedhimtotryanotherway.四.作宾语补足语。例如：•TheteacheraskedustoreadEnglishforhalfanhourinthemorning.•TheteacheroftentellsJimnottospendtoomuchtimeplayingcomputergames.•Pleaseletmehelpyou.动词不定式作宾语补足语，表示宾语所做的动作，可以用动词不定式作宾语补足语的动词有：tell,ask,want,like,invite,encourage,help等。但在let,make,see,watch,hear,feel,notice,have等感官听觉动词或使役动词后面作宾语补足语的动词不定式一般要省略动词不定式符号“to”，可以归纳为以下三种句式：1.不可以省to的不定式作宾语补足语：tell/ask/want/wouldlike/wish/like/invite/encourage/teachsb.todosth.例：•Theteachertoldustocomeearliertomorrow.•Iwantyoutogonow.•Herparentswishhertobeateacher.2.省“to”的不定式作宾语补足语：Let/make/havesb.dosth.•Lettheboygooutnow.•Theboymadethebabycry.see/watch/hear/notice/feelsb.dosth.•Isawthestudentsplaybasketballontheplaygroundyesterday.•Ioftenhearthegirlsinginthenextroom.3.可省可不省的：helpsb.（to）dosth.Ioftenhelpmymother（to）dohousework.否定形式：（1）动词不定式的否定式是直接在to之前加not.例：Tellthemnottoplayfootballinthestreet.（2）省to的动词不定式的否定式是直接在动词前面加not.例：Lettheboynotgo.被动语态：如果将主动语态变为被动语态时，作宾语补足语的动词不定式变为主语补足语，动词不定式则不省“to”，即原来省的再加上，例：•Theboymadethebabycry.•Thebabywasmadetocrybytheboy.Hehasagoodwaytomakehisclasseslivelyandinteresting.五.动词不定式作定语动词不定式作定语常用来修饰名词或不定代词，放于所修饰的词后，为后置定语。例：•Whowasthefirstonetoarrive?•Shehasnopapertowriteon?•ThebestwaytolearnEnglishistouseit.•Whenisthebesttimetoplantvegetables?•Doyouhavesomethingtodrink?*动词不定式（短语）作定语修饰名词时，与其所修饰的词具有一种动宾关系，如果不定式中的动词为不及物动词时，其后应加上一个含义上所需要的介词。例：•Ihavenochairtositon.•Hehasnohousetolivein.Sometimestoo,Iwastooweaktogotoschool.六.作状语:动词不定式及其短语具有副词的特性，可在句中作状语。（1）作目的状语。如：Hestoppedtohavearest.（2）作结果状语。如：Hewokeuptofindeverybodygone.（3）在某些表示喜、怒、哀、乐等的形容词后作原因状语。如：I’msorrytohearyourgrandmaisill.（4）在带有enough或too的句子里作状语，表程度。如：Heisoldenoughtogotoschool.（5）强调动词不定式所表示的目的时，动词不定式可用inorderto或soasto+动词原形，soasto不用于句首。如：Thebusstoppedsoastopickuppassengers.Wh+todo七.不定式和疑问词连用，可以作句子的主语、宾语、表语等。例：•Theproblemiswheretogetacomputer.（表语）•Nooneknowshowtodoit.（宾）•Ireallydon’tknowwhichonetochoose.（宾）•Whenandwheretohavethepartyisnotknown.(主)*不定式和疑问词连用作宾语时有时可以改为宾语从句。例：Idon’tknowwhattodonext.Idon’tknowwhatIshoulddonext.练习：1.Pleasetellhim_______onthewall.A.don’tdrawB.tonotdrawC.nottodrawD.notdraw2.I’dlike________awordwithyou.A.hadB.havingC.tohaveD.have3.Weoftenheardhim_________inhisroom.A.tosingB.singsC.sangD.sing4.Hewasmade_____dayandnight.A.workB.workingC.toworkD.worked5.Hestopped______alook,butsawnothing.A.havingB.tohaveC.haveD.had6.Hesaidhehadanimportantmeeting________.A.attendB.wouldattendC.attendingD.toattend7.Pleasegivemeapieceofpaper________.A.towriteB.towriteonC.writingD.towriteit8.Idon’tknow_______.A.whatdoB.whatwilldoC.whattodoD.dowhat9.Yourradioneeds________.A.toberepairedB.torepairC.repairedD.torepairing10.Pleasetellme_____her.Ihavesomething____her.A.wheretofind,tellingB.wheretofind,totellC.wherecanfind,totellD.wherefinding,telling11.Howhappytheyare______eachotheragain!A.toseeB.seeC.sawD.beingseen12.Theydecided____aletter______theirthanks.A.towrite,expressingB.writing,expressC.write,expressedD.towrite,toexpress