初中英语语法精讲2动词不定式用法

动词不定式用法动词不定式没有人称和数的变化，在句中不能独立作谓语。但动词不定式具有名词、形容词和副词特征，在句中可以作主语、宾语、宾语补足语、定语、表语和状语等多种成分。另外，动词不定式具有动词特点，可以有自己的宾语和状语，组成动词不定式短语。动词不定式的肯定形式是to+do；其否定形式是notto+doo下面以动词不定式在句中的作用来予以详细说明。一.作主语可以直接作主语。如： Toseeistobelieve.但在英语中，常用it作形式主语，真正的主语即动词不定式放在后面。如：It'swrongtoplaytricksonotherpeople.It'sourdutytokeepourenvironmentcleanandtidy.点击规律：动词不定式在句中作主语时，常放在Itis+adj+(forsb.)+(not)todosth句型中，表示说话人对客观事件的决断，意为：做…・.是……的，it仅作形式主语，真正的主语是todosthItisveryinterestingtoread.读书是有趣的Itisusefultoread.看书是有用的Itishealthytoruneveryday每天跑步是健康的Itisalittledifficultyformetoworkoutthisquestion.解出这道题对我来说有点难Itisbadnottofinishhomework.不完成作业是糟糕的Itisbadtobelateforschool.迟到是糟糕的Itis+adj+ofsb+(not)todosth该句型通常表示说话人对客观事件的惊讶、兴奋、懊悔、难过等感叹情绪，与Itis+adj+(forsb.)+(not)todosth的意义不同。Itisverykindofyoutotellmethetruth.你能告诉我事实，真是太好了Itisstupidofhimtodosuchasillything.他做那件傻事，真是太笨了Itisverycleverofyoutoworkoutthisquestion.你能解出这道题目，真是太聪明了Itisverywiseofyoutoreadthisnovel.你看这本小说，真是太明智了这个句型中用介词of而不是for的原因是这里的形容词是用来形容人的品质性格的。类似的词有：careless,careful,clever,considerate,foolish,good,impolite,kind, naughty,nice,silly,stupid,friendly因此区分是用Itis+adj+(forsb.)+(not)todosth还是Itis+adj+ofsb+(not)todosth,要清楚adj修饰的是sb还是todosth例如：Itisniceformetohavebreakfastwithyou(nice是指havebreakfastwithyou这件事)对于我来说，能和你一起吃早餐真好。ItisniceofyoutohelphimwithhisEnglish.(nice是指you,形容人的品质)你帮他补习英语，真是太好了。二.作宾语want,decide,agree,afford,agree,aim,appear,ask,believe,care,claim,decide,demand,desire,determine,expect,fail,happen,hesitate,hope,intend（有打算），learn,long（渴望），manage,offer,pretend,promise,prepare,refuse,seek,swear（发誓），undertake（承担），want,wish等动词后面跟并且只能跟不定式。如：Weagreedtostartearly.Shewantstobeadoctor.love,like,begin,start,hate,prefer等词后面可以接不定式。点击规律：上述动词后面除按不定式外，还可以接动名词，意思无很大区别。提示板：likedoing指经常性动作，而liketodo指一次性的动作。如：Ilikeswimming,butIdon'tliketoswimnow.我喜欢游泳，但我现在不想游。stop,forget,remember,goon,try等词或短语后面可以接不定式。点击规律：上述动词后面按不定式和接动名词意思大不相同。提示板：stoptodosth.：停止一件事，去做另一件事。stopdoingsth.:停止正在做的事forgettodosth：忘记要去做某事（未做）forgetdoingsth：忘记做过某事（已做）remembertodosth：记得去做某事（未做）rememberdoingsth：记得做过某事（已做）goontodosth：接着做另一件事（接下去做与原来不同的一件事）goondoingsth：继续不停的做某事或间断后继续做原来没有做完的事5）trytodosth：试着做某事（实际上意思是努力想做成某事eg:Itriedtoescape,butIfailed.我努力着想逃走，但是没有成功）Trydoingsth：试着做某事（实际上是为了达到另外一个目的， "Sohothere,isn'tit?" "Yes,whynottryturningontheairconditioner?""很热，是吧。”“恩，就是。咱们开开空调吧，看看能不能凉快点儿。”）例句：Whentheteachercamein，thestudentsstoppedtalking；whenhecameout，thestudentsstoppedtotalk.当老师走进来时，学生们停止说话；当老师走出去时，学生们又开始说话。D.在find/feel+it+adj.+todosth,句型中，it是形式宾语，真正的宾语是后面的动词不定式。就是说不定式由it代替，把不定式放到后面去。这可以用这一结构表达：动词（如find,think,consider,feel等）+it+形容词+不定式。如：Sheconsidersitnecessarytomakefriendswithhim.Wefinditdifficulttofinishallthehomeworkbefore9o'clock.Themandownstairsfounditdifficulttogettosleep.Ifeeliteasytorecitethetext.E.动词+疑问代（副）词+不定式：这类动词常见的有advise,decide,findout,forget,inquire,know,learn,see,regard,remember,teach,tell,understand,wonder等。常见的疑问代（副）词有:what,when,where,which,how,whether等。.Hedoesnotknowwhentostart..Youcandecidewhethertocontinueortostop.willshowyouhowtodealwithit.三.作宾语补足语tell,ask,want,order,teach,invite,warn,wish,help,get,wish,help等词后面常接不定式作宾补。如：Itellhimnottogotherebybus.Edison'smothertaughthimtoreadandwrite.let,make,have,see,hear,feel,watch,notice后面接不带to的不定式作宾补。如：Thebossmakesthemwork16hoursaday.Iheardhersinginthenextroom．提示板：若变成被动语态，在上述结构中，不定式符号to要加上。如：Theyaremadetowork16hoursadaybytheboss．Shewasheardtosinginthenextroom.四.作定语：放在被修饰的名词、代词后面例句：Ihavealotofworktodo.Hecoulddonothingtohelptheboy．Therewasreallynothingtofear.Hegavemeaninterestingbooktoread点击规律：动词不定式若在句中作定语，常放在被修饰的名词、代词之后。提示板：如果动词不定式和前面所修饰的词构成动宾关系，若动词是不及物动词，切记不要忘掉介词。如：Ihaveasmallbedroomtolivein.Haveyougotsomepenstowritewith?Maryneedsafriendtoplaywith.Thatgirlhasnothingtoworryabout.Theyhaveastrictteachertolistento.五.表语：放在连系动词be后面例句：Hiswishistobecomeascientist.Thefirstimportantthingistosavethesoldiers'lives.当务之急是抢救战士们的生命。点击规律：动词不定式在句中作表语时，通常对连系动词前面的名词进行诠释说明。六.作状语a.目的状语：放在go,come,use,live,inorder等词后面。如：Icometoseeyou.Herunsfastinordertogetthereintime.b.原因状语：放在sorry,glad,surprised,disappointed,excited等词后面。如：Iamgladtoseeyouhere.Iamsorrytotroubleyou.c.作结果状语。如：Someoftheapplesarehardtoreach.Theroomislargeenoughtohold1000people.7.与what,who,whose,when,where,how等疑问词连用，作宾语、宾语补足语、主语等。如：Idon'tknowwhattodonext.（宾语）Hetaughtushowtousethecomputer.（宾语补足语）It'sstillaquestionhowtogetthere.（主语）8、在动词help之后可用不带to的不定式，也可用带to的不定式。例如：1.Helptheoldlady（to）carrytheheavybox.9、在hadbetter,wouldrather,may/mightaswell,ratherthan,cannotbut等搭配之后，动词不定式也不带to。例如：1.Unlessyoufeeltoilltogoout,Iwouldrathernotstayathometonight.2.Shecouldnotbutcriticizehisfoolishbehaviour.10.在介词but,except之后，如果其前有动词do的某种形式，其后不定式一般不带to,反之则必须带to,表示“只能”。例J如：.Hewilldoanythingexceptworkonthefarm..Therewasnothingleftfortheenemytodobutsurrender..Thespy间谍wasbothhungryandcold；therewasnothingleftforhimbuttogivein.hadnochoicebuttowaittillitstoppedraining.11、下面一些短语是固定搭配，不带to：cannothelpbut,cannotchoosebut,cannotbut,donothingbut,havenothingtodobut。例如：Icannotbutadmirehiscourage.如果上述句中有do,to省略：IdidnothingbutwatchTVlastnight.如果是下面一个固定搭配，就带to：Ihavenochoicebuttogiveupmyidea.12、紧跟在why或whynot之后的动词不定式总是不带to。但是，紧跟在who,what,which,whether等连接词后的不定式带to。例如：Whystandupifyoucansitdown?Whynotaskyourteacherwhenyoudon'tunderstandthemeaning?Youneedn'tdecidewhethertostudyartsorscience.练习：单项选择Thechairlooksveryold,butinfactitisverycomfortableto.A.sit B.sitonC.besat D.besatonThepurposeoftheplanisnottohelptheemployersbutworkforyoungpeople.A.provideB.toprovideC.providingD.providedHearrivedattheofficeearly,agoodexampletotheothers.A.setB.tosetC.tobesetD.havingsetI'mafraidtheywouldnotallowhimhere.A.tosmokeB.smokingC.smokesD.smokeWelookedeverywhereforthekeys,buttheyarenowhereA.tofindB.tohavefoundC.tobefoundD.beingfoundMothertoldmethewaterbeforeIdrankit.A.boilingB.boiledC.boil D.toboilIttookusmorethantwohours thedinnerAprepareBpreparingCtoprepareDtobepreparedPleaseremembertheplantswhileI'maway.A.wateringB.tobewateringC.towaterD.beingwatering

9.wine,firstyoumustpressthegrapes.A.MakingB.TomakeC.TobemakingD.MakeJohnwasmadethecarforaweekasapunishment.A.towashB.washingC.wash D.tobewashingAsaresultofmylaziness,Ifailedmyworkintime.A.andfinishedB.tofinish C.andfinishingD.tofinishedI,llhavetochangemyclothesbeforeIgoout—Idon,twantlikethis.A.toseeB.tobeseeingC.tobeseenD.beingseenTheworkerswantustogetherwiththem.AworkBworkingCtoworkDworkedHepromisedmeanicecar.A.buyB.tobuyC.bought D.tohaveboughtHewasmadeAgoBgoneCgoingDtogoYou,dbetterarestnow.A.tohaveB.have