非谓语动词—动词不定式A.语法要点剖析非谓语动词就是在句子中不能单独作谓语的动词，这样的动词没有人称和数的变化。它包括动词不定式、动词-ing和动词-ed三种形式。㈠动词不定式：由“to+动词原形”构成，其否定形式是“nottodo”,不定式在句子中可作主语、宾语、宾补、表语、状语和定语。1．动词不定式的语法功能⑴．作主语Toseeistobelieve.Itiskindofyoutorepairmybicycle.Itisgoodforustotakepartinphysicallabor.注意：不定式短语作主语时，往往放在谓语之后，用it作形式主语。⑵．作宾语Shewantedtoborrowmybike.IfinditinterestingtostudyEnglish.注意：不定式短语作宾语时，若还带有宾补，往往把不定式放宾补之后，而用it作形式宾语。⑶．作宾补Heaskedmetodotheworkwithhim.注意：在feel,hear,listento,watch,notice,observe,see,have,let,make等词后的补足语中，不定式不带to。但这些句子如果变成被动结构，就必须带to。Ioftenhearhimsingthesong.Heisoftenheardtosingthesong.⑷．作定语ThenexttraintoarriveisfromWashington.Shewasthefirstpersontothinkoftheidea.注意：①若不定式的动词是不及物动词，其后要加适当的介词。Heislookingaroomtolivein.Thereisnothingtoworryabout.②当不定式所修饰的名词或代词是不定式动作的承受者时，不定式的主动语态和被动语态表示不同的含义。Haveyouanythingtobetyped?(动作的执行者是说话者)Ihavealotofthingstoseetothisafternoon.（动作的执行者是句子的主语）⑸．作表语Hiswishistobecomeascientist.Tothedoctor,themostimportantthingistosavepeople’slives.⑹．作状语，表示目的、结果、原因。Hestoppedtohavearest.(表示目的)(Inorder)Tosearchforgold,manypeoplewenttoCalifornia.（表示目的）IoftenreadChinaDaily(soas/inorder)toimprovemyEnglish.（表示目的）注意：soasto不能位于句首。WhathaveIsaidtomakeyousoangry?(表示结果)Shewentabroadnevertoreturn.(表示结果)注意：①不定式和only连用，表示未预料的结果。Thethiefbrokeintothehouseonlytofinditempty.②在so…asto,such…asto,enoughto,too…to等结构中的不定式均表示结果。Heistooyoungtojointhearmy.Heissocarelessastoforgethispen.I’mgladtohearthenews.(表示原因)⑺．作插入语Totellthetruth,Idon’tagreewithyou.常用的这类短语有：tobebrief,tobegin/startwith,tobehonest,tomakethingsworse,etc.⑻．不定式与疑问词who,which,when,where,how,what等连用，在句中起名词作用，可作主语、表语、宾语等。Howtosolvetheproblemisveryimportant.（作主语）Myquestioniswhentostart.（作表语）Idon’tknowwhattodonext.（作宾语）注意：在与why连用时，只用于why或whynot开头的简短疑问句中，后面紧跟的动词不定式不带to。Whynothavearest?Whyworryaboutit?⑼．“介词＋which/whom+不定式”结构通常用作后置定语。Sheisaverynicewomanwithwhomtowork.Withoutfacts,apersoncannotformacorrectopinion,forheneedstohaveactualknowledgeonwhichtobasehisthinking.⑽．省略to的动词不定式①助动词或情态动词后(oughtto,haveto,beto除外)MayIaskyouaquestion?Willyougowithme?②在与why连用时，只用于why或whynot开头的简短疑问句中，后面紧跟的动词不定式不带to。Whynothavearest?Whyworryaboutit?③介词but,except,besides之后跟不定式作宾语时，若介词前有动词do及其变化形式时，不定省略to。Whatdoyouliketodobesidesswim?Hedidnothingbutplaycomputergameslastnight.Ihavenochoicebuttogo.④在hear,listento,watch,see,notice,feel,make,have等词后的补足语中，不定式省略to，但在被结构中，必须带to。Haveyouseenastrangerenterthebuilding?Iheardhimgoupstairs./Hewasheardtogoupstairs.⑤在hadbetter,wouldrather,wouldrather…than等结构后，不定式省略to。Iwouldratherstayathomeratherthangotothecinemawithhim.Youhadbetterstudyhardfromnowon.1．动词不定式的时态和语态如下表所示（以动词do为例）：主动语态被动语态一般式todotobedoing...
