UNIT1UNIT2DISCOVERUSEFULSTRUCTURES不定式课件2021学高中英语人教版选择性必修第三册

语法精讲动词不定式infinitivesTolearnthe

function

of

infinitivesinasentenceTouseinfinitivestocompletetheexercises不定式:是一种非谓语动词。1.非谓语动词:是指那些在句中不能单独充当谓语的动词，2.动词不定式在句中可以作句子除谓语之外的任何句子成分。3.动词不定式的被动形式除了一般形式外还有其完成式和进行式。不定式的定义:不定式的形式:一.基本形式：

to+动词原形二.其否定形式是:“not/nevertodo”/notdo.三.不定式可带宾语或状语构成不定式短语，没有人称和数的变化。主动语态被动语态一般式进行式完成式完成进行式

todo

tobedone

tobedoing

tohavedone

tohavebeendone

tohavebeendoing------------------判断下列不定式在句中作何成分1.Itisimpossibletofinishsomuchhomeworkinaday.2.Toseeistobelieve.3.Hiswishistobeadoctor.4.Iwanttodoitmyself.5.Wefounditdifficulttoworkwithhim.6.Healwayshasalotofmeetingstoattend.7.Heislookingforaroomtolivein.8.Istudyhardtoservethepeoplewell.9.Inordernottobelateshetookabus.不定式作主语通常位于句首，表示具体的某次动作，谓语动词用单数。e.g.Toseeistobelieve.百闻不如一见。

Togetupearlyisnecessary.早起是必要的。______________isveryimportantforeveryoneinsociety. 学习一项技能对社会上的每个人都很重要。______________________inamonthisdifficult.要在一个月内完成这座建筑是困难的。不定式作主语

Tolearnaskill

Tofinishthebuilding2.动词不定式与疑问词who,whom,whose,what,which,when,

where,how等连用构成不定式短语，也可作主语。

e.g.Howtousethecomputeristhequestion.如何使用计算机是个问题。Wheretogohasnotbeendecided.去哪儿还没有定下来。不定式作主语3.当主语较长，谓语较短时，常用it作形式主语放在句首，而将真正的主语—不定式放到谓语的后面。e.g.It’snoteasytoworkouttheproblem.=Toworkouttheproblemisnoteasy.计算出这道题不容易。Itisinteresting______________________.冬季里玩雪是很有趣的。Itisterrible______________________________.目睹轮船沉入大海，真是太可怕了。不定式作主语

toplaywithsnowinwinter

toseetheshipsinkingintotheseait作形式主语代替真正主语不定式常见于以下情况中：Itis+adj.+for/ofsb.todosth.Itis+n.+(forsb.)todosth.Ittakes/took/willtakesb.sometime/moneytodosth.【温馨提示】不定式作主语常用于表示事物的特征，用于此句型的形容词有：easy, hard, difficult, possible, important, impossible, necessary, good, bad, exciting, interesting, surprising等。e.g.It’simportantforustokeepthewaterclean.保持水质清洁对我们来说是很重要的。1)Itis＋adj.

＋forsb.todosth.sb.是todosth.的逻辑主语Itis+adj.+for/ofsb.todosth.不定式作主语常见的此类形容词有：

kind, nice, wise, silly, polite, impolite, friendly, foolish, clever等。e.g.Itisfriendlyofthefamilytotrytomakemefeelathome这家人对我很友好，使我感到宾至如归。2)Itis＋adj.＋ofsb.＋todosth.形容词用来表示不定式的逻辑主语(sb.)的性质、特征或品德不定式作主语常见的名词有：pity, shame, pleasure, one’sduty, one’sjob, fun, joy, goodmanners, badmanners等。Itis+n.+(forsb.)todosth.e.g.Whatapityitisforyoutohavemissedsuchawonderfulfilm.真遗憾你错过了这样一个精彩的电影。  Itmustbegreatfun__________________________.乘宇宙飞船飞往月球一定很有趣。不定式作主语

toflytothemooninaspaceshipIttakes/took/willtake

sb.sometime/money

todosth.做某事花费某人多长时间(钱)e.g.Ittookmeanhourtodomyhomeworkyesterdayevening.昨天晚上我做作业用了一个小时。Itwilltakeusalotofmoney__________________.买那套房子要花费我们很多钱。不定式作主语

tobuythathouse3.如果要说明不定式表示的动作是谁做的

,可以在不定式前加一个由for/of引起的短语,构成__________。2.不定式作主语时,可以用it作_______________.Itis+adj+for

sbtodo……5.Itis+adj+ofsbtodo………（修饰人品形容词）（修饰物的形容词）1.单个不定式作主语，谓语动词_________单数形式主语不定式的复合结构Summary6.Itis+n.+forsbtodo……7.Ittakes/took/willtake

sb.sometime/money

todosth.1.[2019·全国I卷]Itisdifficult_____________(figure)outaglobalpopulationofpolarbears.2.Thenwewillknowhowimportantitis______ustohavemeaninginourlife.3.[2019·天津3月卷]

Comingoutofthisexperience,IrealizeitisOK__________(be)differentfromothers.4.[2018·全国Ⅱ卷]Exerciseenergizesyou,so______ismoredifficulttorelaxandhaveapeacefulsleepwhenyouareveryexcited.【温馨提示】Practice:tofigurefortobeitⅠ.用括号内所给动词的适当形式填空1.Itiswise

(take)suchgiftswithgratitude.2.Hewillfinditiseasy

(make)friendsinthiscity.3.

(get)therebybikewilltakeushalfanhour.4.Itisanoffence

(drop)litterinthestreet.5.When

(leave)forLondonhasnotbeendecidedyet.6.It’snecessaryforyou

(lock)thecarwhenyoudonotuseit.7.Wecan’tafford________(live)insuchabighouse.8.Themanexpectshiswife________(bring)himbreakfastinbedatweekends.9.Afraidof_____________(bite)bysnakes,theboywasafraid________(touch)them.10.JamesWattisknown___________________(invent)thesteamengine.11.Thebookwassaid______________________(translate)intoGermanin1946.12.Themeeting_______________(hold)tomorrowisofgreatimportance.13.Aquarrelseems_____________________(breakout)betweenthetwowomenandtheyarestillglaringateachothernow.totaketomakeTogettodroptoleavetolocktohavebrokenouttolivetobringbeingbittentotouchtohaveinventedtohavebeentranslatedtobeheldⅡ.补全句子1.

isagoodhabit.每天读书是个好习惯。2.

isnice.和他们交朋友真是令人愉快。3.

todomeafavor.你能帮助我真是太好了。4.

doesgoodtoyourhealth.晚饭后散步对健康有好处。5.Itisimpossibleforlosttime

.弥补失去的时间是不可能的。6.Itisdifficultforus

inaquarterofanhour.我们很难在15分钟内完成这篇作文。ReadingbookseverydayTomakefriendswiththemIt’skindofyouWalkingaftersuppertobemadeuptofinishwritingthecompositionⅢ语法填空

Mikedrovetoaremotebordertownalone.Hedidn’tstopthecar1.________(take)abreakalthoughhewasfeelingtired.Asaresult,atrafficaccidentoccurred,whichcausedhim2._________________(trap)insidethecar.Fortunatelyagirlwhohappenedtopassbyvolunteered3.________(save)him,only4.________(find)Mikewascompletelylockedinthecar.Aftercallinganambulance,shemanaged5.________(give)himfirstaid,usingthemethodshehadlearnedatschool.Soon,Mikewasrushedtohospitalinanambulance.Ittookhimthreemonths6.___________(recover)fromhisinjuries.ThegirlnamedMaryfeltpleased7.____________(do)suchagreatthing,thoughsherealizedthecarmayhaveexploded.Wheninterviewed,shesaid,“I’vealsometwithatrafficaccident.Akindpasser-bysavedmylifebuthewaskilled.Iwastheonlyone8._______________(survive)thecrash.Themanwassaid9.______________(work)ontheroadhelpingpeopleinneedfortenyears.Iwastoomovedeventospeakwhenhearingthestory.Therefore,Idetermined10.________(stay)hereandgivepeopleinneedahelpinghand.”tostaytotaketobetrappedtosavetofindtogivetorecovertohavedonetohavesurvivedtohaveworkedWhydoeshecomesoearly?DiscoveryHisaimistotakethefirstbus.1结构

Be(am/is/are/was/were)+不定式e.g.Thepurposeofeducationistodevelopafinepersonalityinchildren.2功能（1）解释主语描述的行为或说明该行为带来的结果。主语多为duty/wish/hope/idea/plan/ambition/dream/work/job/ability/attempt/chance/desire/need/opportunity/refusal/wish/aim/purpose/decision/choice...等名词e.g.Mydreamistobeasinger.Hisworkistocleantheclassroomeveryday.不定式作表语（2）表示“安排、命令、决定、劝告、意愿、禁止”等e.g.IamtosetoutforChinanextweek.下周我要动身到中国去。（安排）Youaretohaveaface-to-facetalkwiththem.你应该和他们当面谈一谈。（劝告）Childrenarenottosmoke.儿童不准吸烟。（禁止）不定式作表语

3.两种特殊用法（1）不定式短语tolet，toblame，toseek等常用主动形式表示被动含义Thehouseistolet.Whoistoblameforthepopulationdeclineofthetigersinthatarea?Thereasonforglobalwarmingisnotfartoseek.全球变暖的原因不难找到。（2）当主语部分含有动词do的某种形式时，作表语的不定式可省略toAnythingwecandois(to)guarantee

itwillbedeliveredontime.Intheeveningtheonlythinghedidwas(to)readontheblog.不定式作表语4.当主语含定语从句且其先行词为代词all或形容词最高级theleast,themost时：+系动词+不定式作句子的表语。egAllhewantedwastobeleftalone.

TheleastIcanexpectistohavethisdayalltomyself.5.当不定式作表语时，句子主语可以使what引导的主语从句。egWhatIwanttodonowis(to)havearest.不定式作表语3.Medicalexpertssaythemosteffectivewaytopreventthespreadofdiseaseisforpeople________(wash)theirhandswithsoapandwater.4.Thenextstepis________surethatyouknowexactlywhatisrequired.5.Thepurposeofeducationis__________(develop)afinepersonalityinchildren.towashtomaketodevelop1.Themottoofthelittleboywhowassufferingfromamusclediseasewas_______(live)onedayatatime.2.Itisyou,includingyourcousin,that____________(blame)forthelossofthegoldenchance.tolivearetoblameCompletethesentences.1.要是他们问我这个问题，我该怎么回答呢？________________iftheyaskmethequestion?2.她应该为所发生的事情受到责备。_________________forwhathashappened.3.你要做的事情是面对现实。Thethingforyoutodo________________.4.我筋疲力尽，想能马上就去度假。Iamexhaustedandtiredout.WhatIwanttodo____________________.WhatamItosaySheistoblameis(to)facethefactsistotakeaholiday不定式放在及物动词后，用作宾语e.g.

WebegintoreadEnglishat6:30a.m.

Sheforgottoclosethedoor.不定式作宾语常用动词不定式作宾语的动词有：

want,plan,hope,wish,learn,decide,wouldlike,begin,start,try,need,forget,choose,prepare,agree,promise,manage,encourage,fail,happen,mean,refuse,offer,learn，etc.forget,remember,prefer,like等动词除了跟

不定式作宾语，可以跟动名词做宾语吗？挖坑动词不定式作宾语的注意事项不定式作宾语时，如带有宾语补足语，则要把不定式放到后面，用it作形式宾语，构成“主语+动词+it+宾补（形容词、名词）+不定式”结构。如：

e.g.Ifounditnecessarytotalktohimagain.IfounditimportanttolearnEnglish.不定式作宾语think/find/consider+it+adj.+todo1、Don’tforget_________________.(关灯)2、Ihappened________whenhecalledme.（出去）3、Idon’twant________________.(依赖别人）4、Samislearning________________.(怎样开车）5、Wepromise__________theenvironment.(保护)toturnoffthelighttogoouttodependonothershowtodriveacarPracticetoprotectCompletethefollowingsentences.1.I_______________(希望收到…来信)yousoon.2.John________________(不想当)thehostofthecharityshow.3.They’re____________(试着解决)theproblembyhimself.4.Millionsofpeople_________________(已学会使用)computers.

hopetohearfromdoesn’twanttobetryingtosolvehavelearnedtouseRainbowexpectsyoutohaveabrightfuture.考点一：跟“不定式”作宾语补足语的动词／动词短语allow,ask,beg,cause,encourage,expect,force,intend,invite,order,persuade,prefer,remind,tell,want,warn,wish,callon,dependon,require,forbid,advise,recommend,,permit,等sbtodosthe.g.Havingfinishedherproject,shewasinvitedbytheschool_________(speak)tothenewstudents. 不定式作宾补:tospeakrequire,forbid,advise,recommend,allow,permit,encourage+sb.+todosth.(接动词的不定式作宾补)

但如果直接用动词作宾语时，还是用todo吗？require,forbid,advise,recommend,allow,permit,encourage+doingsth.(接动名词作宾语)Iadviseyoutohavearest.Iadvisehavingarest.不定式作宾补难点:五看

watch

see

lookat

observe

notice三使

let

make

have

二听

listento

hear一感觉:

feel当遇到下列动词时,不定式省略to:被动语态不省to）

不定式作宾补难点:1.Johnwasmade

thecarforaweekasapunishmentA.towashB.washingC.washD.tobewashing2.Thepatientwaswarned

foodaftertheoperation.A.toeatnotB.eatingnotC.nottoeatD.noteating3.Internetbarsmustn’tletanybody

badthings,especiallychildren.A.watchB.towatchC.watchingD.watchesPracticeACAIwaswatchingtheclockallthroughthemeeting,asIhadatrain______(catch).(2017·天津卷)我在会议期间一直看表，因为我要赶火车。不定式作定语tocatch考点一：不定式与其所修饰的词之间常是动宾关系Heisalwaysthefirst_________attheschoolandthelasttoleavetheschool.他总是第一个(人)到校，最后一个(人)离校。

考点二：序数词，形容词最高级，thelast,theonly

等后或被这些词修饰的名词或代词后，常用不定式作定语。toarrive不定式作定语Theability_________(express)anideaisasimportantastheideaitself.表达观点的能力与观点本身同等重要。(湖南卷)考点三：被修饰词是抽象名词时，常用不定式作定语。如ability,chance,idea,hope,wish,fact,excuse,promise,attempt,way等。toexpress不定式作定语时，应放在被修饰词的后面。e.g.Wehavealotofhomework

todo.如果不定式中的动词是不及物动词,则不定式中要有介词.e.g.Heislookingforaroom

tolivein.Thereisnothing

toworryabout.something,anything,nothing…+adj.+todoe.g.Ihavesomething

interesting

totellyou.不定式作定语:1.Doyouhaveanythingmore_______﹙要说﹚?2.Shehasalotofwork_______﹙做﹚everyday.3.Theoldmanhasahouse_________﹙住﹚.4.Sheisaniceperson__________﹙共事﹚.tosaytodotoliveintoworkwithPractice不定式作状语___________(enjoy)theconvenienceofdigitalpayment,manyseniorcitizensstartedtousesmartphones.(2019·江苏卷)为了享受数字支付的便利，很多老年人开始使用智能手机。Toenjoy考点一：作目的状语。可用soasto/inorderto替换，但soasto一般不可置于句首，意为“为了；想要”。不定式作状语Tomtookataxitotheairport,only________(find)hisplanehighupinthesky. (四川卷)

汤姆乘出租车去了机场，结果却发现他要乘坐的飞机已飞入高空。tofind考点二：作结果状语。常用于下列结构中：onlytodo(表示意想不到的结果)；enoughtodo(足够做……)；too...todo...(太……而不能做……)；so/such...asto...(如此……以至于……)等不定式作状语Theoldmansatinfrontofthetelevisioneveryevening,happy________(see)anythingthathappenedtobeon.(全国卷)tosee考点三：作原因状语。常与表示喜怒哀乐、运气好坏的形容词(happy,ashamed,sorry,glad,delighted,angry,discouraged,shocked...)连用1.Toseeyouisglad.=It’sgladtoseeyou.2.Iwanttoseeyou.3.Iwanthimtoseeyou.4.Myhopeistoseeyou.5.Heisthemantoseeyou.6.I’mgladtoseeyou.7.Iwenttoseeyou.8.Hewentsoearlyastoseeyou9.Howtosolvethisproblemisveryimportant.（作主语）(作宾语）（作宾补）(作表语）（作定语）（作原因状语）（作目的状语）（作结果状语）和疑问词连用Summary

(eat,giveup,finish,explain,tell)1.Myteacherwasmade___________histeachingbecauseofpoorhealth.togiveupexplaining/tobeexplainedtobefinishednottoeat3.Wefinditimpossibleforthework_____________aheadoftime.4.Thepatientwaswarned____________oilyfoodaftertheoperation.2.Thesentencewants_______________________