非谓语动词在句中充当除谓语以外的句子成分的动词形式叫做非谓语动词。非谓语动词分为三种形式:不定式、动名词和分词(分词包括现在分词和过去分词)不定式、动名词和现在分词都有时态和语态的变化.不定式主动语态被动语态与谓语动词的关系一般式TodoTobedone动作发生在谓语动作之后进行式Tobedoing与谓语动作同时发生完成式TohavedoneTohavebeendone动作发生在谓语动作之前动名词主动语态被动语态与谓语动词的关系一般式DoingBeingdone与谓语动作同时发生完成式HavingdoingHavingbeendone动作发生在谓语动作之前现在分词主动语态被动语态与谓语动词的关系一般式DoingBeingdone与谓语动作同时发生完成式HavingdoneHavingbeendone动作发生在谓语动作之前不定式一、不定式的作用1、作主语不定式作主语时,谓语用单数。往往用it作形式主语,把不定式放在谓语后面。如:Ittookustwohourstofinishthejob.Itisimpossibleforustogetthereontime.Itisverykindofyoutohelpus.注意:(1)其他系动词如look,appear等也可用于此句型。(2)当不定式作主语的句子中又有一个不定式作表语时,不能用Itis…to…的句型。试比较:Itistonegatemyownideatobelievehim.(错)Tobelievehimistonegatemyownidea.(对)(3)Itis+adj.of/forsb.todosth.结构中,当不定式的逻辑主语和前面的形容词可以构成系表结构时,用of,否则用for.2、作宾语(1)动词+不定式。如:Hemanagedtoescapefromthefire.Ifindithardtogetalongwithhim.(it作形式宾语)注:下列动词通常用不定式作宾语:want,try,hope,wish,need,forget,know,promise,refuse,help,decide,begin,start,learn,agree,choose,get等(2)动词+疑问词+to,“特殊疑问句+不定式”相当于名词,作宾语。如:Idon’tknowwhattodonext/howtodoitnext.Ican’tdecidewhentogothere.注意: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语补足语之后,用it作形式宾语。如:Ifinditnecessarytolearnaforeignlanguage.3、作宾语补足语(1)动词+宾语+不定式(todo)。如:Hewarnedmetobecareful.IwantyoutospeaktoTom.Whatmakesyouthinkso?(不带to的不定式)注:可以用动词不定式做宾补的动词有:ask,tell,order,want,get,wouldlike,like,advise,invite,allow,help,wish,warn,expect,prefer,encourage(2)表见解、看法的动词结构可为:动词+宾语+tobe的不定式结构。如:WeconsiderTomtobeoneofthebeststudentsinourclass.Thebookisbelievedtobeuseful.(被动语态)(3)There+不定式。如:Wedidn’texpecttheretobesomanypeoplethere.我们没料到会有那么多人在那里。注意:(1)有些动词需用as短语作补语,像regard,think,believe,take,consider。如:WeregardTomasourbestteacher.我们认为汤姆是我们最好的老师。Marytookhimasherfather.玛丽把他当作自己的父亲。(2)在动词feel(一感),hear,listento(二听),have,let,make(三让),notice,see,watch,observe,lookat(五看)(即:吾看三室两厅一感觉)等后面的补足语中,不定式不带to,但变为被动语态后,必须带to。如:Theysawtheboyfalloffthetree.Theboywasseentofalloffthetree.(3)help后面作宾语补足语的不定式可以带to,也可以不带to.Ioftenhelphim(to)cleantheroom.Ihelpedhim(to)findhisthings.4、作定语不定式作定语,修饰名词或代词,不定式和它所修饰的名词之间有逻辑上的主谓关系、动状关系、同位关系或动宾关系。不定式通常要放在这些被修饰的词后。如:Ihavealotofworktodo.(动宾关系)Heislookingforaroomtolivein.(动状关系)Heisthefirstpersontothinkoftheidea.(主谓关系)Hehasgotachancetogoabroad.(同位关系)注意:1.不定式的逻辑主语是句子的主语时,不定式用主动形式表被动。如:Doyouhaveanythingelsetosay?2.如果作定语的不定式是一个短语,则要保留不定时短语中的副词或介词。如:Ineedapentowritewith.(Iwillwirtewiththepen)(我需要一直钢笔写字)Ihavealittlebabytolookafter.(Imustlookafterthelittlebaby)(我有一个婴儿要照看)作状语,表示目的、结果、原因等,有时还有一些固定搭配的不定式短语,如inorderto,soasto,so…asto,such…asto,….enoughto,too…to等。(1)做目的状语,to,onlyto(仅仅为了),inorderto,soasto,so(such)….asto…(如此···以便···)如:Heransofastastocatchthefirstbus.他飞快地跑以便赶上第一班车。Hecametotheschooltoseehisson.(2)作结果状语,表事先没有预料到的,要放在句子后面。如:Hehurriedtothepostofficeonlytofinditwasclosed.Hesearchedtheroomonlytofindnothing.(3)做原因状语。如:Wewereveryexcitedtohearthenews.I’mgladtoseeyou.(4)做条件状语。如:Toturntotheleft,youcouldfindapostoffice.5、作表语不定式可放在be动词后面,构成表语。如:Thequestionishowtoputitintopractice.Myquestioniswhentoleave.Hisdreamistobeadoctor.Herworkistolookafterthebabies.注意:1.不定式在句中作表语时,对应的谓语动词用单数。2.当助于是不定式时,表语不能用Ving形式,可用不定式。如:Toseeistobelieve.(眼见为实)6、独立结构。如:Totellyouthetruth,Idon’tagreewithyou.Tomakemattersworse,itbegantorain.二、不定式的时态和语态1、不定式的时态(1)现在时:有时与谓语动词表示的动作同时发生,有时发生在谓语动词的动作之后。如:Heseemstoknowthis.Ihopetoseeyouagain.(2)完成时:表示的动作发生在谓语动词表示的动作之前。如:I’msorrytohavegivenyousomuchtrouble.Heseemstohavecaughtacold.(3)进行时:表示动作正在进行,与谓语动词表示的动作同时发生。如:Heseemstobeeatingsomething.(4)完成进行时:表示动作从过去某个时间开始,一直延续到现在,并有可能持续下去。如:Sheisknowntohavebeenworkingontheproblemformanyyears.2、不定式的语态当不定式的逻辑主语是其动作的承受者时,就用被动式。如:Hewasseentoenterthehall.HeaskedtobesenttoworkinTibet.三、省to的动词不定式1、情态动词(除ought外,oughtto)2、Wouldrather,hadbetter.3、感官动词see,watch,lookat,notice,observe,hear,listento,smell,feel等后作宾补,省略to.注意:在被动语态中to不能省略掉。如:Isawhimdance.Hewasseentodance.Thebossmadethemworkthewholenight.Theyweremadetoworkthewholenight.4、使役动词let,have,make.5、由and,or和than连接的两个不定式,第二个to可以省去。如:HewantstomovetoFranceandmarrythegirl.6、Help可带to,也可不带to,helpsb.(to)dosth.7、Why…/Whynot…8、But和except前是动词do时,后面出现的动词用不带to的动词不定式。试比较:Hewantstodonothingbutgoout.Hewantstobelieveanythingbuttotakethemedicine.9、通常在discover,imagine,suppose,think,understand等词后,可以省去tobe.如:Heissupposed(tobe)nice.他应该是个好人。——Iusuallygotherebytrain.——Whynot______byboatforachange?AtotrygoingBtryingtogoCtotryandgoDtrygoingPauldoesn’thavetobemade______.Healwaysworkshard.AlearnBtolearnClearnedDlearning四、动词不定式的否定式。如:Tellhimnottoshutthewindow.ShepretendednottoseemewhenIpassedby.动名词(动名词具有动词和名词的特征,在句中作主语、表语、宾语和定语)一、动名词的作用1、作主语谓语用单数。It代替动名词作主语,常用于如下结构:It’snogood/usedoing···如:Seeingisbelieving.Playingwithfireisdangerous.It’snogoodwaitinghere.2、作宾语Ienjoylisteningtomusic.Heoftenpracticesplayingthepianointheevening.Heisfondofplayingbasketball.Hehasgivenupsmoking.Wouldyoumindturningdownyourradioalittle,please?(1)只能接动名词作宾语的动词:admit,advise建议,risk,appreciate,envy嫉妒,avoid避免,consider考虑,delay延迟,deny否认,dislike不喜欢,enjoy,escape逃避,excuse原谅、宽恕,finish完成,forgive原谅,understand理解,giveup放弃,imagine想象,keep保持,mind介意、在乎,miss未达到,practise训练,putoff推迟,resist抵抗,suggest建议、暗示can’thelp禁不住,can’tstand无法忍受