动词不定式的用法.doc

1动词不定式的用法概念:动词不定式由to+动词原形构成。这里的to是不定式标志,没有词义。不定式具有名词、形容词或副词的某些语法功能,又有动词的时态和语态的特点及作用。可以做主语、宾语、宾语补足语、表语、定语、状语。一、作主语动词不定式作主语时,句子的谓语动词常用单数,其位置有以下两种:(1)把不定式置于句首。如:Togettherebybikewilltakeushalfanhour.(2)用it作形式主语,把真正的主语不定式置于句后,常用于下列句式中。如:①It+be+名词+todoIt'sourdutytotakegoodcareoftheold.②Ittakessb+sometime+todoHowlongdidittakeyoutofinishthework?③It+be+形容词+b+③中,常用表示客观情况的形容词,如:easy,difficult,hard,important,possible,fortable,necessary,better;thefirst,thenext,thelast,thebest,toomuch,toolittle,notenough④It+be+形容词+ofsb+④中,常用careless,clever,good,foolish,honest,kind,lazy,nice,right,silly,stupid,wiserude,clever,foolish,thoughtful,thoughtless(欠考虑的;不考虑的),brave,considerate(考虑周到的),selfish(自私的)等表示赞扬或批评的词。在不定式前的sb,可看作其逻辑主语。这一句式有时相当于Sbis+形容词+todo句式,如:It'skindofyoutohelpmewithmyEnglish.=YouarekindtohelpmewithmyEnglish.⑤Itseems(appears)+形容词+,这显得太自私了。注意:1)其他系动词如,look,appear等也可用于此句型2)不定式作为句子主语时,动词用单数形式。3)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…的句型对应性:。二、作宾语1)以下动词后,只能跟不定式作宾语afford(付得起),agree(同意),aim(力求做到),appear(显得),arrange(安排),ask(要求),attempt(试图),care(想要),choose(决定),claim(声称),condescend(屈尊),consent(准许),decide(决定),demand(要求),determine(决心),endeavor(竭2力),expect(期待),fail(未履行),help(帮助),hesitate(犹豫),hope(希望),learn(学会),manage(设法),neglect(疏忽),offer(主动提出),plan(计划),prepare(准备),pretend(假装),proceed(接着做),promise(答应),prove(证明),refuse(拒绝),resolve(解决),seem(觉得好像),swear(发誓),tend(往往会),threaten(威胁),undertake(承诺),volunteer(自愿做),vow(发誓),want(想要),wish(希望)举例:。。2)动词+疑问词+不定式decide,know,et,learn,remember,show,understand,see,wonder,hear,findout,explain,。Therearesomanykindsoftape-recordersonsalethatIcan',我都拿不定主意买哪一种。注意:疑问词带不定式在句中作主语时,谓语动词用单数。Thequestionishowtoputitinto