初中英语语法词性动词不定式(二)第二节动词不定式的用法一、不定式结构作主语1.不定式前置1)Derive［A］mineralresourcesfrom［B］sedimentaryrock［C］isa［D］majormodernindustrialactivity.2)inthematriculationforpostgraduateinashorttimeisrealyahardnut.［A］Tomakehighscores［B］Tomakelowgoal［C］Tothehighscores［D］Makethelowgoals2.上述形式一般情况不多见，作为考试的规范英语，如果不定式较长，显得头重脚轻，则可由代词“it”作形式主语(形式主语“it”不能由“that”或“this”等其他代词代替)，而将不定式放到后面Itisreallyahardnuttogethighscoresinthematriculationforpostgraduateinashorttime.3)Johnadmittedthatit'salwaysdifficult.［A］forhimbeingontime［B］beingontimeforhim［C］forhimtobeontime［D］ontimeforhim4)Itisdifficultforme［A］tobeconcentrating［B］whilesomeone［C］isusing［D］avacuumcleaner.3.不定式后置的情况不仅限于动词是系动词，也适用于其他动词Ittookusagreatdealofeffortstofinishthattask.ItmadehimextremelyhappytogetcontactwithhisfamilyinTaiwansincetheyseparatedmorethan40yearsago.4.不定式结构所表示的动作是谁做的，即不定式的逻辑主语，通常可以在特定的上下文中能看出，也可以通过带“for＋名词短语”辨出Itisquiteimportantforustoreadgoodbooksduringtheperiodofgeneralreview(总复习).Itisnotdifficultforthosewhostudymathswelltopasstheexam.5.在某些形容词(如careless,clever,considerate,foolish,good,impolite,kind,naughty,nice,silly,stupid等)作表语时，不定式后可以加of来引导出其逻辑主语Itisverykindofyoutohelpme./Itisstupidofhimtodosuchasillything.间或也可用for＋theretobe表示(而且there后面的不定式只能是tobe)。It'sagreatpityfortheretobemuchtroubleinthecompany.二、不定式作宾语不定式作宾语有两种：一种是及物动词后直接跟带to的不定式；另一种是“动词＋疑问词＋带to的不定式”1.动词＋带to的不定式结构只能跟动词不定式的动词，常见的有：afford,agree,aim,appear,arrange,ask,believe,care,claim,decide,decline(拒绝),demand,desire,determine,endeavor,expect,fail,hesitate,hope,intend,learn,long,manage,mean(想要),offer(表示愿意做…),pretend,promise,refuse,seek(试图),swear,undertake,wish(想要)等。5)Werefusethatthereareinsufficientfundsinthegreatvaults(银行保管库)ofthisnation.［A］tobelieve［B］tobebelived［C］beliving［D］havebelived6)Thegreenturtlehasbeenknownover2，000milestoreturntoanestingsite.［A］inthenavigating［B］thenavigation［C］tonavigate［D］navigation7)Forthe［A］firsttimeVenusianscientistsmanagedlanding［B］asatelliteontheplanetEarth,andithasbeensending［C］backsignalsaswellas［D］photographseversince.8)ThedayispastwhenChineseuniversitiesandcollegestogivehighschooldiplomastoallwhositthroughfouryearsofinstruction,regardlessofwhetheranyvisibleresultscanbediscerned.［A］afforded［B］affording［C］toafford［D］canafford从上例我们可以看出afford一般与can和can't或could和couldn't连用。2.动词＋疑问代(副)词＋不定式这类动词常见的有：advise,decide,discuss,findout,forget,inquire,know,learn,regard,remember,see,settle,teach,tell,think(=consider),understand,wonder等。这些疑问代(副)词有what,when,where,which,how,whether等，但不包括why，如：???????????????????????????Hedoesnotknowhowtogothere???????????????????whentospeakbeforestrangers.???????????????????who(m)tovisit.???????????????????whichonetochoose.??Youcandecidewhethertogoforwardorstayhere.?????????????????whentoseeadoctor.??Iwillshowyouwhattodo.??????????????????wheretogo.??????????????????howtodealwithit.其中，1)和2)中不定式的逻辑主语仍是句子的主语，分别为He和You；而3)中...
