it用作形式宾语的四个特殊句式?当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时，通常会在宾语补足语前使用形式宾语it，而将真正的宾语移至句末，此时it仍只起先行引导作用，本身无词义。
其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”。
如：Ifinditdifficulttodothejobwell.我发现做好这件事不容易。
Ithinkitbestthatyoushouldstayhere.我认为你最好住这儿。
Wethinkitnousecomplaining.Hemakesitarulenevertoborrowmoney.Ithinkitnoneedtalkingaboutitwiththem.Hefeltitimportant?tolearn?Englishwell.能这样用的动词有：为"6123结构"。
6指主句中常用的动词：123考点）：1.动词据传闻，国防部长不久就要辞职。
等。
2.动词like,enjoy,love,hate，Wereallyappreciateitwhensheofferedtohelp.她来帮忙了，我们十分感激。
I’dpreferitifIdidn’thavetodo somuchwork.要是我不必做那么多工作，好就太好了。
3.动词+prep+it+that-从句。
that引导的宾语从句不能直接作介词的宾语。
如：Seetoitthatyou’renotlateagain.注意千万不要再迟到。
Looktoitthatthisdoesn’thappenagain.注意不要再发生这种事。
Ican’tanswerforitthathewillcome.我不能保证他会来。
Youmayrelyonitthathe’llcometomeetyou.你放心，他会来接你的。
Youmaydependonitthatweshallalwayshelpyou.（尽管放心，我们会随时帮你的。
）Wouldyouseetoitthatshegetshomeearly?（你负责保证她早到家，好吗？）Heinsistedonitthathewasinnocent.（他坚持说自己是无辜的。
）说明：能用于此结构的动词不多，常见的有seeto,lookto,insiston,stickto,dependon,answerfor 等。
4.动词+it+介词短语+that-从句。
由及物动词与介词组成的固定搭配中，宾语从句若作该动词的宾语时，须借用it。
如：IoweittoyouthatIamstillalive.多亏有你我才仍然活着。
Itookitforgrantedthathewouldhelpus.我认为他会帮助我们的。
Ileaveittoyourownjudgementwhetheryoushoulddoit.（我让你自己判断这事是否该做。
）Weoweittoyouthattherewasn’taseriousaccident.（多亏了你才没有发生严重事故。
）说明：能用于此结构的动词不多，常见的有takeitforgranted,bringittosb’sattention,oweittosb,keepitinmindthat…等。
5.动词+it+as+名词、形容词、从句能用于此句型中的动词有：试比较下列高考题，选出最佳答案：A.thisB.thatC.itD.heA.thisB.thatC.itsD.itA.thisB.thatC.heD.itA.heB.whichC.sheD.it(2005A.it(2005A.thatB.itC.thisD.him代词(2006浙江卷)4._______isourbeliefthatimprovementsinhealthcarewillleadtoastronger,moreprosperous economy.A.AsB.ThatC.ThisD.It(2006山东卷)24.I’dappreciate____ifyouwouldliketoteachmehowtousethecomputer.A.thatB.itC.thisD.you___feltfunnywatchingmyselfonTV.(2007全国卷II)A.OneB.ThisC.ItD.That_____________worriesmethewayhekeepschanginghismind.(2007山东卷)A.ThisB.ThatC.WhatD.ItHedidn’tmake________clearwhenandwherethemeetingwouldbeheld.(2007天津卷)A.thisB.thatC.itD.these(2009浙江卷)—I’vereadanotherbookthisweek.—Well,maybeisnothowmuchyoureadbutwhatyoureadthatcounts.A.thisB.thatC.thereD.it(2010全国卷II14).Thedoctorthought____wouldbegoodforyoutohaveaholiday.A.thisB.thatC.oneD.it(2010辽宁卷33).Thefactthatshewasforeignmade_____difficultforhertogetajobinthatcountry.A.soB.muchC.thatD.it（2011山东卷）24.Thetwogirlsaresoalikethatstrangersfind______difficulttotellonefromtheother.??????A .it????B.them????C.her??????D.that（2011?A.that????B.it?????C.his????D.him（2011天津卷）模拟练习：A.This;thatB.That;thatC.It;thatD.He;thatA.thatB.thisC.itD.themA.Istru10.Wethink_______ourdutytopaytaxestoourgovernment.A.thatB.thisC.itsD.itKey:高考真题:1-8CDDDDADC模拟练习:1-5CCBCD6-10DDDAD学生版试比较下列高考题，选出最佳答案：1.Is_______necessarytocompletethedesignbeforeNationalDay?A.thisB.thatC.itD.he2.Idon’tthink_______poss ibletomasteraforeignlanguagewithoutmuchmemorywork.A.thisB.thatC.itsD.it3.Does_______matterifhecan’tfinishthejobontime?A.thisB.thatC.heD.it4.Tom’smotherkepttellinghimthatheshouldworkharder,but_______didn’thelp.A.heB.whichC.sheD.it5._______isafactthatEnglishisbeingacceptedasaninternationallanguage.A.ThereB.ThisC.ThatD.It6.Ihate_______whenpeopletalkwiththeirmouthsfull.A.itB.thatC.theseD.them7.Don’t_______thatallthosewhogetgoodgradesintheentranceexaminationwillprovetobeth emostsuccessful.A.takeasgrantedB.takethisforgrantedC.takethatforgrantedD.takeitforgranted8.Ilike_______intheautumnwhentheweatherisclearandbright.A.thisB.thatC.itD.one9A.itB.sheC.whichD.he代词A.thatB.itC.thisD.him代词onomy.A.AsB.ThatC.ThisD.It12.I’dappreciate__A.thatB.itC.thisD.you13.________feltfunnywatchingmyselfonTV.A.One15.A.this16.—A.it????B.them????C.her??????D.that20.Whydon’tyoubring______tohisattention.?A.that????B.it?????C.his????D.him21.Wefeel______ourdutytomakeourcountryabetterplace.A.it?????????????B.this??????????????????C.that??????????????D.one模拟练习：1._______happened_______heisunfitfortheoffice.A.This;thatB.That;thatC.It;thatD.He;that2.Wetook_______forgrantedthattheywouldacceptouradvice.A.thatB.thisC.itD.them3._______thatthescientistwillgiveusatalknextmonth?A.IstrueB.IsittrueC.It’strueD.It’struly4._______doesn’tmattermuch_______dressyouaregoingtowear.A.This;thatB.That;whoC.It;whichD.It;who5._______isgoingtoAmericaforfurtherstudy.A.HeissaidthatB.PeoplesaidthatheC.ItwassaidheD.Itissaidthathe6.Theyaregoodfriends._______isnowonderthattheyknoweachothersowell.A.ThisB.ThatC.ThereD.It7.Is_______possibletoflytothemooninaspaceship?A.thisB.thereC.thatD.it8.Sheliked_______whenhekissedher.A.himB.thatC.oneD.itA.ItB.ThereC.ThoseD.OneA.thatB.thisC.itsD.it。