动词不定式、动名词用法要点讲解详细内容1 .不定式作主语动词不定式作主语时，句子的谓语动词常用单数，其位置有以下两种：(1) 把不定式置于句首。如：Togettherebybikewilltakeushalfanhour.(2) 用it作形式主语，把真正的主语不定式置于句后，常用于下列句式中。如： Itbe名词todoItsourdutytotakegoodcareoftheold. Ittakessb+sometime+todoHowlongdidittakeyoutofinishthework? Itbe形容词forsbtodoItisdifficultforustofinishwritingthecompositioninaquarterofanhour. Itbe形容词ofsbtodoItisstupidofyoutowritedowneverythingtheteachersays. Itseems(appears)形容词todoItseemedimpossibletosavemoney.在句型中，常用表示客观情况的形容词，如：difficult,easy,hard,important,impossible,necessary等；在句型中，常用careless,clever,good,foolish,honest,kind,lazy,nice,right,silly,stupid,wise等表示赞扬或批评的词。在不定式前的sb，可看作其逻辑主语。这一句式有时相当于Sbis形容词todo句式，如：ItskindofyoutohelpmewithmyEnglish.=YouarekindtohelpmewithmyEnglish.2 .动名词作主语Learningwithoutpracticeisnogood.动名词作主语时，也常用It句式。如： Its+nogood(nouse,fun,apleasure,awasteoftime)+doingItsnogoodreadingindimlight.Itsnousesittingherewaiting. Its形容词doingItsdangerousswimmingintheseainwindydays.这样用的形容词有expensive,nice,tiring等，但important,necessary则不适用于这种结构，应用不定式代替，如：Itsimportantforyoutokeepfit. Thereisno+doingThereisnosayingwhatwillhappennext.在这一结构中，动名词后常带宾语，相当于Its impossible to 结构。3 .动词不定式和动名词作主语的区别不定式作主语经常表示具体动作，常与特定的动作执行者联系在一起；而动名词作主语经常表示抽象动作，经常不与特定的动作执行者联系在一起。如：Itsnogoodeatingtoomuchfat.Itsnogoodforyoutoeatsomuchfat.动名词结构作主语，可以用名词或代词属格形式作逻辑主语。如:Itsnouseyourpretendingthatyoudidntknowtherules.二、作宾语1 .不定式作宾语以下动词后，只能跟不定式作宾语。如agree,ask,aim,arrange,choose,decide,demand,expect,fail,help,hope,lean,long,manage,offer,plan,prepare,pretend,promise,refuse,wish等，这些词大部分可接that引导的从句。如：Idecidedtoaskformymoneyback.IdecidedthatIwouldaskformymoneyback.Whenourvisittothefarmwasover,weexpectedtostartbackonfoot.Whenourvisittothefarmwasover,weexpectedthatwewouldstartbackonfoot.当复合宾语中的宾语是不定式时，先用形式宾语it代替不定式，把不定式置于补语之后，即：主语动词it补语todo句式。如：Wethinkitquiteimportantforustolearnaforeignlanguagewell.Hefeelsithisdutytohelpthepoor.介词but,except,besides+todo(do)在这种句型中，如介词前有动词do，后面应接不带to的不定式；如无do，则接to不定式，即带do不带to，带to不带do。如：Theenemysoldiershadnochoicebuttogivein.OnSundayafternoonIhadnothingtodobutwatchTV.2 .动名词作宾语以下动词后，只能接动名词作宾语，如：admit,appreciate,consider,delay,enjoy,finish,keep,imagine,mind,miss,practise,resist,risk,save,suggest,dontmind,giveup,insist,on,putoff等。如：Isuggestspendingoursummervacationinaseasidetown.Youmustgiveupsmoking,foritdoestoomuchharmtoyourhealth.动名词作介词的宾语Ishouldgotoattendthebirthdaycelebrationinsteadofstayingathome.WhataboutinvitingLiJuntomakeaspeech?动名词前的介词有时可以省略，如：havedifficulty(in)doing,havenotrouble(in)doing,losenotime(in)doing,prevent/stop(from)doing,thereisnouse(in)doing等。3 .部分动词后面，既可接动词不定式，也可接动名词作宾语，意义不变。如：begin,continue,start,hate,like,love,need,require,want等。在need,require,want后接-ing形式，表示被动意义，也可接不定式，但要用被动形式，如：Yourhandwritingneedsimproving(tobeimproved).hate,love,like接不定式表示特定的未来事件，接动名词表示目前正在进行的活动或一般的行为。在下列情况下，一般要用不定式：hate,like,love前有would(should)时，如：Idliketohaveacupofcoffee.当谓语动词begin,continue,start等是进行式时，如：Thestudentsarestartingtoworkonthedifficultmathsproblem.begin,continue,start与know,understand等状态动词连用时，如：Isoonbegantounderstandwhatwashappening.4.advise,allow,encourage,forbid,permit等动词后接动名词作宾语，或带不定式作宾语补足语。如：Ourteachersdontpermitourswimminginthelake.Ourteachersdontpermitustoswiminthelake.分部分动词后接不定式或动名词时，意义差别较大，应根据句子语境选择使用。 forget,remember,regret后接不定式，表示现在或未来的动作，接动名词表示动作已经发生。如：Dontforgetfoposttheletterforme.HaveyouforgottenmeetingherinBeijingAirport?Remembertoclosethewindowsbeforeyouleave.Irememberwritinghimaletterayearago.Weregrettotellyouthatallofyouarenotinvitedtoattendthemeeting.Theyregrettedorderingthesebooksfromabroad. meantodo打算做某事doing意味着Imeanttocatchupwiththeearlybus.Thismeanswastingalotofmoney. trytodo设法尽力做某事doing试着做某事Youshouldtrytoovercomeyourshortcomings.Tryworkingoutthephysicsprobleminanotherway. stoptodo停下一件事去做另一件事（不定式作目的状语）doing停止做某事Onthewaytotheairport,Istoppedtobuyapaper.Youdbetterstoparguinganddoasyouaretold. canthelpdoing禁不住todo不能帮助干Theycouldnthelpjumpingupatthenews.SorryIhavelotsofworktodo.SoIcanthelptomakeuptheroomforyou. goontodo做不同的事或不同内容的事doing继续不停地做某事，指同一动作的继续Hewentontotalkaboutworldsituation.他接着又谈了世界形势。Wellgoonfightingsolongasthereisoppressionintheworld. leaveofftodo离开某地去干什么（目的状语）doing停下某事Itstimetoleaveofftalkingandtostartacting.Theyleftofftogofishing.三、做表语不定式作表语表示具体动作或将来动作；动名词作表语表示抽象的一般行为。 Tobekindtotheenemyistobecrueltothepeople. Mychiefpurposeistopointoutthedifficultiesofthematter. WhatIwouldsuggestistoputoffthemeeting.当主语和表语都是不定式时，其含义一是条件，一是结果（例）。当主语是aim,duty,hope,idea,mistake,plan,purpose,suggestion等为中心词的名词词组（例）时，或以what引导的名词性分句（例）,不定式说明主语的内容。 Ourworkisservingthepeople. Whathelikesistakingawalkaftersupper. ThestorytoldbyMr.Wangisinteresting.句动名词作表语，与主语部分可以转换，如Servingthepeopleisoutwork,而句中是现在分词作表语，说明主语的性质、状态，现在分词具有形容词的各种特征，另外，动名词作表语还应与进