不定式作宾语1)动词+不定式affordaimappearagreearrangeaskbedecidebothercarechoosecomedaredemanddesiredetermineexpectelectendeavorhopefailhappenhelphesitatelearnlongmeanmanageofferoughtplanpreparepretendpromiserefuseseemtendwaitwishundertake举例：Thedriverfailedtoseetheothercarintime.司机没能及时看见另一辆车。Ihappentoknowtheanswertoyourquestion.我碰巧知道你那道问题的答案。2）动词+不定式；动词+宾语+不定式ask,beg,choose,expect,hate,helpintendlike,love,needprefer,prepare,promise,want,wish…Iliketokeepeverythingtidy.我喜欢每件东西都保持整洁。Ilikeyoutokeepeverythingtidy.我喜欢你年使每件东西都保持整洁。IwanttospeaktoTom.我想和汤姆谈话。IwantyoutospeaktoTom.我想让你和汤姆谈话。3）动词+疑问词+todecide,know,considerforget,learn,remember,show,understand,see,wonder,hear,findout,explain,tellPleaseshowushowtodothat.请演示给我们如何去做。Therearesomanykindsoftape-recordersonsalethatIcan’tmakeupmymindwhichtobuy.有这么多的录音机，我都拿不定主意买哪一种。注意:疑问词带不定式在句中作成分时，谓语动词用单数。Thequestionishowtoputitintopractice.问题是怎样把它付诸实施.不定式作补语1)动词+宾语+不定式(todo)adviseallowappointbelievecausechallengecommandcompelconsiderdeclaredriveenableencouragefindforbidforceguesshireimagineimpelinduceinforminstructinvitejudgeknowlikeorderpermitpersuaderemindreportrequestrequireselectsendstatesupposetellthinktraintrustunderstandurgewarn例句：a.Fatherwillnotallowustoplayonthestreet.父亲不让我们在街上玩耍。b.Webelievehimtobeguilty.我们相信他是有罪的。Find的特殊用法：Find后可用分词做宾补，或先加形式宾语，再加形容词，最后加带to的动词不定式。find后也可带一个从句。此类动词还有get，have。Ifoundhimlyingontheground.Ifounditimportanttolearn.IfoundthattolearnEnglishisimportant.典型例题:Thenextmorningshefoundtheman___inbed，dead.A.lyingB.lieC.layD.laying答案：A.find的宾语后面，用分词或分词短语，起宾语补足语作用。现在分词表达主动，也表达正在进行，过去分词表达被动。2)to+be的不定式结构，作补语的动词。Acknowledge,believe,consider,think,declare(声称),discover,fancy(设想),feelfind,guess,judge,imagine,know,prove,see(理解),show,suppose,take(以为),understandWeconsiderTomtobeoneofthebeststudentsinourclass.我们认为汤姆是班上最好的学生之一。典型例题CharlesBabbageisgenerallyconsidered___thefirstcomputer.A.toinventB.inventingC.tohaveinventedD.havinginvented答案：A.由considertodosth.排除B、D。.此句只说明发明这一个事实，不定式后用原形即可。而C为现在完成时，发明为点动词一般不用完成时，且此处也不强调对现在的影响，因此不选C。3)tobe+形容词Seem,appear,besaid,besupposed,bebelieved,bethought,beknown,bereported,hope,wish,desire,want,plan,expect,mean…Thebookisbelievedtobeuninteresting.人们认为这本书没什么意思。4)therebe+不定式believe,expect,intend,like,love,mean,prefer,want,wish,undrstandWedidn’texpecttheretobesomanypeoplethere.我们没料到会有那么多人在哪里。注意：有些动词需用as短语做补语，如regard,thinkbelieve,take,consider.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。.不定式作主语1）It’seasy(forme)todothat.我做这事太容易了easy,difficult,hard,important,possible,impossible,comfortable,necessary,better;thefirst,thenext,thelast,thebest,toomuch,toolittle,notenoughIt’ssonicetohearyourvoice.听到你的声音真高兴。It’snecessaryforyoutolockthecarwhenyoudonotuseit.当你不用车的时候，锁车是有必要的。2)It’sverykindofyoutohelpus.他帮助我们，他真好。Kind,nice,stupid,rude,clever,foolish,thoughtful,thoughtless,brave,considerate(考虑周到的),silly,selfish(自私的)例句:Itwassillyofustobelievehim.我们真愚蠢，竟然相信了他。Itseemedselfishofhimnottogivethemanything.他不给他们任何东西，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)不定式作为句子成分时，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)Toseeistobelieve.百闻不如一见。(错)Itistobelievetosee.
