初中动词不定式专题讲解及练习(全面)VIP免费

小菜学英语Practicemakesperfect!语法：动词不定式动词不定动式是一种非谓语动词形式，它没有人称和数的变化，在句子中不能作谓语，但可以作除谓语之外的其它任何句子成分（主语、表语、宾语、宾语补足语、定语和状语）；动词不定式具有名词、形容词和副词的特征，同时还保持动词的某些特点，既可以有自己的宾语和状语，动词不定式和它的宾语和状语构成不定式短语。一、构成：todo.否定式nottodo二、常见时态：一般时todo进行时tobedoing完成式tohavedone完成进行式tohavebeendoing三、动词不定式在句子中的成分1、作句子的主语：现实中常用it作形式主语，而把真正的主语动词不定式（或短语）后置。比较下列句子Tolearnfromyourfriendsisimportant.=Itisimportanttolearnfromyourfriends.Toleavewithoutsayinggoodbyeisimpolite.=Itisimpolitetoleavewithoutsayinggoodbye.TochatwithMissWhiteisapleasantthing.=ItisapleasantthingtochatwithMissWhite.Towalktoschooltakesmetenminutes.=Ittakesmetenminutestowalktoschool.句型总结Itis+adj.+ofsb.todo…=sb.is\are+adj.+todo…在以某些表示人的品质、特征等的形容词（如kind、good、nice、wrong、clever、right等）作表语时，不定式之前常加一个引起的短语，说明不定式指的是谁的情况（可以理解为某人的好，坏，聪明，愚蠢，对，错等等）。Itisverykindofyoutohelpme.It’snotpoliteofhimtospeaktooldpeoplelikethat.Itis+adj.+forsb.todo…≠sb.is\are+adj.+todo…如果要说明不定式表示的动作是谁做的，则在不定式前加一个for引起的短语，即不定式的逻辑主语。Itisnecessaryforustostudyhard.ItiseasyforhimtospeakEnglish.动词不定式作主语练习1.It'sourduty_________theroomeveryday.A.tocleanB.cleanedC.cleanD.cleans(甘肃省)2.It'shardforus_____Englishwell.A.learnB.learnsC.tolearnD.learning(江西省)3.建造这座立交桥将花费工人们一年多的时间。Itwill______theworkersoverayear_________theflyover.(北京市海淀区)4.It'sverynice_____youtogetmetwotickets_________theWorldCup.A.for，ofB.of，forC.to，forD.of，to(安徽省)KEYS:1.A2.C3.take,tobuild4.B2、作句子的表语：不定式放在be动词后面，用作表语如：Herdreamistobeapoliceman.Myjobistohelpthepatient.Yourtaskistocleantheclassroom.Mydreamistoownarobot.Thedoctor’ssuggestionistotakemoreexercise.Thebestwayistotalktoyourparents.1/12小菜学英语Practicemakesperfect!HisplanistotraveltoBeijingthissummer.Mypurposeistohelpyousolvethisproblem.3、作句子的宾语：不定式放在及物动词后，用作宾语。能跟不定式作宾语的动词（及物）很多，常见的有want,like,hate,wish,hope,prefer,try,ask,start,begin,decide,learn,choose,agree,expect,remember,forget,plan,decide,wouldlike,need,choose,agree,promise,refuse,setout,manage,pretend,Iwanttogohome.Theworkersdemandedtogetbetterpay.Theybegantoreadandwrite.Sheforgottoclosethedoor.HewantedtoborrowmyCDplayer.IhopetospeakEnglishwell.Theworkersdemandedtogetbetterpay.Ihopetohearfromyousoon.Johndoesn’twanttobethehostofthecharityshow.Theyaretryingtosolvetheproblembyhimself.Millionsofpeoplehavelearnedtousecomputers.有些动词既可跟不定式作宾语，也可跟动名词作宾语，但含义不同：forgettodosth.忘记要做某事forgetdoingsth.忘记曾经做过某事stoptodosth.停下来去做某事stopdoingsth.停止做某事goontodosth.继续做另一件事goondoingsth.继续做原来在做的事needtodosth.需要做某事needdoingsth.需要被做Don’tforgetoturnoffthelightsbeforeleaving.Fathermuststopsmoking.Thisbikeneedsrepairing/mending.注意1：动词不定式作宾语时如带有宾语补足语，则要把不定式放在后面，用it作形式主语，构成“主语+动词+it+宾补（形容词、名词）+不定式”结构Ifounditnecessarytotalktohimagain.IfounditimportanttolearnEnglish.Ifonditdifficulttolearnphysics.注意2：常用带to...