不定式用法总结

动词不定式的基本用法归纳一、动词不定时的形式：肯定式：todosth否定式：nottodosth.被动式：tobedone一般被动否定式：nottobedone完成主动式：tohavedone完成否定式：nottohavedone完成被动式：tohavebeendone完成被动否定式：nottohavebeendone,动词不定式的基本用法归纳,二、动词不定式的用法1作主语A动词不定式作主语，谓语动词用单数形式。如：Toseeistobelieve.(Seeingisbelieving.)Mychiefpurposeistopointoutthedifficultiesofthematter.Herwishistobecomeadoctor.B不定式或不定式短语作主语时，常用it作形式主语，构成“Itis+形容词(+forsb.)不定式”结构。Itisimpossibleforhimtogiveupsmoking.,2.作宾语,A动词后直接不定式作宾语的动词有许多，如want,decide,intend,fail,wish,export,pretend,choose等等。Imeantogothereatonce.B.不定式短语作宾语时，如果还带有宾语补足语，往往把不定式短语放在宾补之后，而用it作形式宾语。句型为“主语+find(feel,think,believe,consider,etc)+it+形容词/名词+todosth”。Ithinkitnecessarytoreportthethingtotheteacher.Ifinditinterestingtoworkwithhim.C动词不定式还可以用作介词宾语，但仅限于介词except和but（除了）。常用句型有：Thereisnothingtodobut+动词原形donothingbut+动词（除做.之外别无选择）canbut+动词原形（只能原形(“只有做)havenochoicebuttodo，只得）cannothelp/choosebut+动词原形(不能不）,but+不定式的用法不定式在介词but,except,besides,otherthan后面时,如果这些介词之前有行为动词do(非助动词)的各种形式时,那么这些介词后面的不定式不带to,否定带to。e.g.Shecoulddonothingbutcry.Whatdoyouliketodobesidesswim?Ihavenochoicebuttowait.Therewasnothingformetodootherthanwaituntilthemeetingwasover.IhadnothingtodobutwatchTV.,当句子的谓语动词是cant,canthelp,cantchoose等结构时,but,except,besides后的不定式to也省略。Wecantbutadmirehisbravery.Wecantchoosebutwait。SheissuchalovelygirlthatIcanthelpbutloveher.,注意:but作“除了以外”解时,若前面部分有do,did,done时,but之后接dosth.反之,后接todosth.Hecandonothingbutwait.Hewantednothingbuttoplayinthepark.,3作表语,动词不定式作表语，一是主语有不定式充当；二是主语由抽象名词充当。Toteachistolearn.Myjobistohelpthepatient.【注意】如果在主语中（通常在主语从句或修饰主语的定语从句中）又实意动词do时，作表语的动词不定式省略to。AllIwanttodonow(WhatIwanttodonow)isfillmystomach.4作宾语不足语【注意】在感官动词（see,hear,feel,listento,notice,watch,observe等）和使役动词（let,have，make）后的补足语中，不定式不带to。但这类句子变成被动语态时，必须带to。Isawhimplayinthepark.Hewasseentoplayinthepark.Thebossmadethosemenworkdayandnight.Thosemenweremadetoworkdayandnight.,Hewasseentobreakthewindow.可后接动词不定式作宾补的动词有：advise,allow,ask,hear,order,see,tell,want,wish,expect,watch等。Thedoctoradvisedhernottoeattoomuchsugar.Iwishyoutogotothemeetingwithme.Thegovernmentcallsonustoincreaseourproduction.,believe,consider,count,declare,deny,feel,find,guess,imagine,judge,know,prove,realize,suppose,think等动词后可接tobe型不定式作宾补。Hedeclaredhimselftobeacollegestudent.他自称是名大学生。Thepoliceprovedhimtobeathief.警察局证实他是小偷。,hope,demand,suggest等动词不能后接动词不定式作宾补。Ihopemysonwillbebacksoon.Sheadvisesustohaveadiscussionaboutit.Shesuggeststhatwe(should)haveadiscussionaboutit.,5定语,1、不定式与被修饰的名词往往构成逻辑上的关系。如名词为不定式的逻辑主语，构成主谓关系；若名词为逻辑宾语，则构成动宾关系；Heisnotthefirstemployeetoarriveattheofficethismorning.TherewillnotbeenoughspacetostandinontheearthIhavesomebooksforyoutoread.2、作定语的不定式与所修饰的名词之间是动宾关系，不定式动词又是不及物动词时，应在该动词上加上一个介词，如;Hehasanicepentowritewith.Heislookingforaroomtolivein.Heissaidthebestwaytotravelbyisonfoot.,动词不定式作定语，应位于所修饰词语之后，即：作后置定语。Haveyougotanythingtoeat?(toeat修饰anything，位于其后)下列名词后常接动词不定式作定语：ability,attempt,chance,courage,decision,effort,failure,promise,way,wish等。Butshegaveupthechancetogoabroad.由only,first,last,next以及序数词或形容词最高级修饰的名词后，也常接不定式作定语。Whowasthelastonetoleavetheclassroomlastnight?,6.作状语,不定式作状语时，可表示目的，原因，结果或条件。如;Imverygladtohearthenews.（原因)不定式作目的状语时，常可与to,toorderto,soasto连用。Hegotupearlysoasnottobelate.不定式可以跟在表语的形容词之后作状语。Thequestionisdifficulttoanswer.。有些不定式短语可以做独立成份，通常放在句首，有时置于句中或句未，须用逗号的开。,Icameheretoseeyou.（目的）Wewereveryexcitedtoseeourfootballteamwon.（原因）Petersavedagirlslifeonhiswaytoworkandthenhurriedtohisoffice,onlytobetoldbythebossthathewasfiredbecausehewaslateagain.(出乎预料的结果）Tolookathim,youwouldlikehim.（条件）Tolearnaforeignlanguagewell,youmustspendalotoftimeandeffortonit.（目的）,作目的状语，还可以使用inorder(not)to