It作形式主语和形式宾语的用法详解

it作形式主语和形式宾语it既可作人称代词，用来表示动物或无生命的物体等，也可以作无人称代词，在句中作主语，表示“时间”、“距离”、“天气”等。它还可以引导强调句，使语气得以加强。此外，it在句中能作引导词，充当句子中的形式上的成分，如形式主语、形式宾语等。㈠it作形式主语：it作形式主语时没有具体的意义，而只是帮助把真正的主语移到句子后部去，使句子显得平稳一些。it作形式主语时，可以代替三种形式：不定式、动名词和主语从句。1.it代替不定式短语常用于下列句型中：It+be+形容词+（for/ofsb.）todosth.It+be+名词+todosth.Ittakessb.sometimetodosth.干…花了某人…时间It'suptosb.todosth.干…是某人的职责或义务如：①Itiseveryone'sdutytoobeythelaw.遵守法律是每个人的义务。（it作形式主语，代替不定式短语toobeythelaw）②ItisdifficultforaforeignertolearnChinese对于一个外国人来说，学习汉语是困难的。（it作形式主语，代替不定式短语tolearnChinese）③Itisnotrighttousetheseplacesasrubbishdumps把这些地方用来倒垃圾是不对的。（it作形式主语，代替不定式短语tousetheseplacesasrubbishdumps）④Ittookthemayeartobuildthebridge.建这座桥花了他们一年的时间。（it作形式主语，代替不定式短语tobuildthebridge）⑤Itisbadmannerstostareatpeople.瞪着眼睛看人是不礼貌的。（it作形式主语，代替不定式短语tostareatpeople）⑥Itisuptoustohelpthoseinneed.帮助那些有困难的人是我们的责任。（it作形式主语，代替不定式短语tohelpthoseinneed）⑦Itisnotuptoyoutotellmehowtodomyjob.我怎样干我的工作不用你来多嘴。（it作形式主语，代替不定式短语totellmehowtodomyjob）♦Itbe+形容词+forsb.todosth.与Itbe+形容词+ofsb.todosth.：如果句型中的形容词描述的是sb.的品质、品格，在逻辑上可以作sb.的表语，则sb.前应用介词of，否则就用for。如：①It’snecessaryforustouseashort-waveradiotopickuptheprogrammes.我们用一台短波收音机收听这些节目是必要的。②It’simportantforustolearnEnglishwell学好英语对我们来说是重要的。③It'skindofyoutohelpme.感谢你对我的帮助。（=Youarekindtohelpme.）④Itwasfoolishofhimtogiveupthejob.他放弃那工作是愚蠢的（=Hewasfoolishtogiveupthejob.）it代替动名词短语：动名词作主语用后置形式的情况远不及不定式那么普遍，常限于nogood,nouse,useless,waste等词的后面。①Itisnogood/usehavingacarifyoucan'tdrive.如果你不会开车，有车也没用。（it作形式主语，代替动名词短语havingacar）②ItisawasteoftimewatchingTV.看电视是浪费时间。（it作形式主语，代替动名词短语watchingTV）③Itisnouseaskinghim.问他没有用。 （it作形式主语，代替动名词短语askinghim）④Itisnousetalkingtohimaboutit.和他谈这事没有用。（it作形式主语，代替动名词短语talkingtohimaboutit）it代替主语从句：这个主语从句可以用连词that引导，也可以用连接代词或连接副词引导。如：①Itwasclearthattheyhadnodesireforpeace7R清楚他们没有和平的诚意。（it作形式主语,代替主语从句thattheyhadnodesireforpeace）②Itisdoubtfulwhethershewillbeabletocome.她能否来还很难说。（it作形式主语,代替主语从句whethershewillbeabletocome）③Itwasclearenoughwhatshemeant.她的意思是够清楚的。（it作形式主语,代替主语从句whatshemeant）@Ithasn’tbeenmadeclearwhenthenewroadistobeopenedtotraffic.还没明确宣布新路什么时候通车。（it作形式主语，代替主语从句whenthenewroadistobeopenedtotraffic）⑤Itisamysterytomehowitallhappened.这都是怎么发生的对于我来说还是一个谜。（it作形式主语,代替主语从句howitallhappened）用it作形式主语，把真正的主语从句移至后面的常见句型有：.Itisapity/ashame/afact/anhonour/goodnews/nowonder/awonder...that...如：①Itwasapitythattheengineercouldn'tcome.可惜工程师没能够来。②Itisawonderthathecontinuestogamblewhenhealwaysloses!令人惊讶的是他一直输还一直赌。③（Itis）nowonder（that）youwerelate!难怪你来晚了。④Itisashamethattherainspoiledourpicnic.真可惜，这场雨把我们的野餐给搅了。⑤ItisafactthatEnglishisbeingacceptedasinternationallanguage.英语被认为是国际语言，这是一个事实。.Itis+形容词(如：strange/natural/surprising/obvious/true/fortunate/wonderful/funny/possible/impossible/likely/unlikely/clear/unusual/certain/important…)that…如：①Itiscertainthathewillwin.他一定会取胜。Itisimportantthatweshouldlearnfromeachotherandhelpeachother.我们应当互相学习，互相帮助，这是很重要的。Itwasobviousthatthechildhadbeenbadlytreated很显然那个孩子受过虐待。Itislikelythathewillringmetonight.他今晚可能给我打电话。⑤Itisstrangethatheshouldhaveleftwithouttellingus.真奇怪，他也没说一声就走了。⑥Itisunlikelythattheirgroupwillgetaheadofus.他们小组不会赶到我们前头去。.Itseems/happened/turnedout/suddenlystruckme/occurredtome…that…如：①IthappenedthatIwasn,ttherethatday.恰好那天我不在那里。②Itseemsthathisideaismorepractical.看起来他的意见更实际一些。ItsuddenlyoccurredtomethatIknewhowtosolvethatproblem.我忽然想起我知道怎样解决那个问题。.It+be+过去分词(如：said/reported/announced/decided/expected/hoped/known/believed...)that...如：①Itishopedthatthenumberofdeerwillgreatlyincreaseverysoon.(ft当于：Peoplehopethatthenumberofdeerwillgreatlyincreaseverysoon)人们希望鹿的数目将会很快增加。②Itissaidthatnothinghasbeendoneaboutit.据说至今对此没采取任何措施。Itisreportedthatmorethantwentypeoplewerekilledinthatbusaccident.据报道在那次的公共汽车事故中有二十多人丧生。Itisknownthatheisoneofthebestteachersinourschool.大家都知道他是我们学校最好的教师之一。Itisbelievedthatthefloodthereisthebiggestin100years.据认为那儿的洪水是百年来最大的洪水。*注意要在Itissuggested/required/desired/ordered/proposed...that...的主语从句中用虚拟语气：(should)+动词原形如：①Itisrequestedthathegiveaperformanceattheparty.有人请求他在聚会上表演一个节目。②Itissuggestedthatweshouldgeteverythingreadybytonight议一切在今晚准备好。③Itisorderedthattheradiobesentthereatonce.据命令，这台收音机要立刻送到那里去。♦Itdoesn'tmatter+连接代词或副词…Itdoesn'tmaketoomuchdifference +连接代词或副词…如：①Itdoesn'tmatterwhetherhecomesornot.他来还是不来都没关系。②Itwon'tmakemuchdifferencewhetheryougotodayortomorrow.你今天去也好，明天去也好，关系不大。㈡it作形式宾语：it作形式宾语时，可以代替三种形式：不定式、动名词和宾语从句。it作形式宾语时，需具备两个条件：真正的宾语是不定式、动名词或从句有宾语补足语具备了这两个条件，形式宾语it一定要用。it代替不定式短语think/find/feel/consider/make/regard…+it+形容词/名词+不定式短语如：①Ifinditpleasanttoworkwithhim.（it作形式宾语，代替不定式短语toworkwithhim）我觉得和他一起工作很愉快。Theyfeltitdifficulttofinishtheworkinsuchashorttime.（it作形式宾语，代替不定式短语tofinishtheworkinsuchashorttime）他们认为在这么短的时间内完成这项工作是困难的。③Shethinksitherdutytohelpus.（it作形式宾语，代替不定式短语tohelpus）她觉得帮助我们是她的责任。④Ithinkitmyhonortobeinvitedtospeakhere.（it作形式宾语，代替不定式短语tobeinvitedtospeakhere）我觉得应邀在这儿演讲是我的荣耀。Tomdidn'tfinditdifficulttowritelettersinChinese.（it作形式宾语，代替不定式短语towritelettersinChinese）汤姆发现用汉语写信不难。Allthesenoisesmadeitimpossibleformetogoonwiththework.（it作形式宾语，代替不定式短语togoonwiththework）这些噪音使我无法继续工作。it代替动名词短语（这只限于少数句型，在多数情况下用不定式时更多一些）如： ①Theprofessorconsidersitnogoodreadingwithoutunderstanding.这位教授认为阅读而不理解没有益处。 ②Doyouconsideritanygoodtryingagain?你觉得再试会有好处吗？③Hefoundituseless（nouse）arguingwithhim.他发现和他辩论没有用。④Hethoughtitabsolutelysenselessattemptingtheimpossible.想做不可能的事情，他认为是完全没道理的。⑤Idon'tthinkitworthwhilegoingtosuchaplace.到这样一个地方去我看是不值得的。it代替宾语从句：如：①Weallthoughtitapitythattheconferenceshouldhavebeencancelled.会议取消了我们都感到很遗憾。②Itookitforgrantedthattheywerenotcoming.我想他们准是不会来的了。③I’llseetoitthateverythingisreadyintime.我负责使一切都按时准备好。㈢含it的常用句型英语中有一些固定句型中含有it,应注意这些句型的使用。1.Itbe+被强调部分+that/who+其他成分强调句型可以强调一个句子的主语、宾语、表语及状语等成分。如果被强调的成分是表示人的词，可以用that或who（whom）连接其他成分；被强调的成分是表示人以外的词，例如表示事物、时间或地点的词，用that连接其他成分。例如我们可以用强调句型强调下列句子的主语（如⑴）、宾语（如⑵）、地点状语（如⑶）及时间状语（如⑷）ImetPeterinJapanlastyear.(1)Itwas I_ who/thatmetPeterinJapanlastyear.⑵ItwasPeterwhom/thatImetinJapanlastyear.⑶ItwasinJapanthatImetPeterlastyear.⑷ItwaslastyearthatImetPeterinJapan.*not…until也可用于强调句型例1MrBrowndidn,tcomebackuntileleveno,clock.可变为：Itwasnotuntileleveno,clockthatMrBrowncameback.例2Theraindidn,tstopuntilmidnight.可变为：Itwasnotuntilmidnightthattherainstopped.*强调句也可变为特殊疑问句例1Itwasin1949thatthePRCwasfounded.可变为：WhenwasitthatthePRCwasfounded?例2Yourdadworkedinthisfactorytwoyearsago.可变为：Wherewasitthatyourdadworkedtwoyearsago?2It5s+地点状语+that… （强调句）It,s+地点名词+whereIt,s+地点名词+where…(定语从句)如:（thetown为地点名词，定语从句）这是我出生的镇子。②ItwasinthetownthatIwasborn.（inthetown为地点状语，强调句型）我出生在这个镇子。t's+时间名词+when…（时间状语从句） It's+时间状语+that…（强调句）如：①Itwasat8o'clockthathereturned.（at8o’clock是时间状语，强调句）他是在八点钟回来的。②Itwas8o'clockwhenhereturned.（8o'clock是时间名词，时间状语从句）他回来的时候是八点钟。ifitisconvenienttoyou如果你方便的话如：Ifitisconvenienttoyou,youcanstarttomorrow如果方便的话，你明天可以动身。believeitornot信不信由你如：①Believeitornot,I'llgoabroadnextmonth不管你信还是不信，我下个月要出国。②Believeritornot,wewereleftwaitingintherainfortwohours.信不信由你我们冒雨等了两个小时。It'stimethat…did/shoulddo…定语从句）如： ①ItistimethatIwentandpickedupmydaughterfromschool我该去学校接我女儿放学了。②It'shightimethatwestopped/shouldstopthispractice我们的确该停止这种做法了。Itis/hasbeen…since…did…（时间状语从句）如：Itisjustaweeksincewearrivedhere.我们来这里已一星期了。Itwon'tbe…before…用不了（多长时间）就会...Itwillbe...before…得过（多长时间）才...Itwasn't…before…没过（多长时间）就……口. Itwas...before…过了（多长时间）才...①Itwillbealongtimebeforewefinishthetask.我们还需要很长时间才能完成这项任务。①Itwillbealongtimebeforewefinishthetask.我们还需要很长时间才能完成这项任务。②Itwasn'tlongbeforehelearnedtousethecomputer.不久他就学会使用计算机了。③Itwassometimebeforehetoldmeaboutthisaffair.过了一段时间之后他告诉了我这件事。④Itwon'tbelongbeforewemeetagain.不久之后我们还会再见面的。㈣易混用其他句型英语中有一些句型不含it,但却易被误用了it，常见的有以下句型:•Thereissomething/nothingwrong/thematterwithsb./sth.如：Thereisnothingwrong/thematterwithhim.He'sjustpretending.他没什么事，他只是在装呢。Thereisnodoubtabout…对…毫不怀疑Thereisnodoubtthat…对…毫不怀疑如：①Thereisnodoubtabouthissuitabilityforthejob.毫无疑问，他适合这个工作。②Thereisnodoubtaboutthefact.关于这个事实毫无怀疑。③Thereisnodoubtthatheishardtodealwith. 毫无置疑他很难对付。Thereisnoneed(forsb.)todosth.没必要…如：①TherewasnoneedforhimtoremaininParis.他没有必要继续留在巴黎。②Thereisnoneedforyoutostartyet.你现在还不必动身。.Thereisno/apossibilitythat 没可能/有可能(=Itisimpossible/possiblethat…)如：①Thereisapossibilitythatthetrainmaybelate.可能火车要晚点。②Thereisnopossibilitythatwe'llseehimthisweekend.我们本周末不可能见到他。.Thereisachancethat…可能…如：Thereisachancethatthesickchildwillgetwell.这个生病的孩子可能会好起来的。.Therebeno/somedifferencesbetween...and 和...之间没/有区别如：Therearesomedifferencesbetweenthetwolanguages. 这两种语言之间有些区别。.Afterwhatseemed+时间如：Afterwhatseemedaverylongtime,thewoundedsoldiercamebacktolife.在经过似乎很长的一段时间之后，那个受伤的士兵苏醒了过来。.Therebedifficulty/trouble(in)doingsth. 干…有困难如：herewasnodifficultyinfindinghim.找到他没费什么事。习题演练：.isreportedthathegotsevengoldmedals.A.ThatB.WordC.ItD.News.Howlongtofinishthework?A.youwilltakeB.willyoutakeC.youwilltakeitD.willittakeyou.noneedforustodiscusstheproblemagain.Ithasalreadybeensettled.A.IthasB.TherehasC.Itis D.Thereiswasdisappointedwiththeplay.Ihadexpectedtobemuchbetter.A.that B.this C.one D.itdon,tthinkpossibletomasteraforeignlanguagewithoutmuchmemorywork.A.itB.that C.its D.this.Doesmatterifhecan,tfinishthejobontime?A.thisB.itC.heD.that.——Doyouneedmyruler?——No,thanks.I’vegotmyself.A.itB.each C.one D.theone.——Whichpersondoyoumean?——whowearsanewgoldwatch.A.Theone B.OneC.Each D.It9.ItthreeyearssinceIleftEngland.A.hasbeenB.wasC.hadbeenD.willbetwon'tbelongtheislandtoourmotherland.A.when,returnsB.before,willreturnC.since,returns D.before,returns11.Howmanyyearsisityourfamilymovedhere?A.after B.since C.before D.until12.isapitythatyouforgotbothheraddressandhertelephonenumber.A.It B.There C.This D.That13.Isawnomorethanonecopyleftinthebookshop.Willyougoandbuy?A.it B.some C.any D.one.Willyouseetothattheluggageisbroughtback?A.me B.yourself C.it D.them.ItthatshehaslostinterestinstudyingEnglish.A.seemedB.appears C.looks D.remains.happenedthatImetoneofmyfriendsyesterday.A.IB.ThatC.ItD.How.Ithinkrightthatyoudidn'ttellhimthebadnews.A.itB.itsC.youD.that.tosaywhichoneIshouldchoose.A.That'shard B.Itishard C.TherenouseD.Itnogood.surprisedmemostwasthatshehadbecomeafamoussinger.A.That B.It C.What D.This.willtakeyoualotoftimetofindhiminthecrowd.A.It B.I C.We D.They.Hefelttoworkforhumanrightsandprogress.A.ithisduty B.hisduty C.thatisaduty D.thatishisduty.PeopleinthewestmakesaruletobuyChristmaspresentsfortheirrelativesandfriends.

A.thatB.itC.thisD.ThethingA.thatB.itC.thisD.Thething.needsfurtherdiscussionwhetherwe'llbuildalibraryornot.A.We B.He C.It D.Thething24.isnogoodwithoutdoinganything.A.This,talkingB.It,totalkC.It,talkingD.That,totalk25.isnodifferencebetweenthem.A.ThereB.WhereC.ItD.What26.Wasitthattheysaw?A.sheB.thatsheC.herD.herself27.beingSunday,thelibrarywasclosed.A.ThatB.ItisC.ItD.This28.Itwaseveningwearrivedthere.A.thatB.whenC.thisD.since29.Itwasinthevillagenowisasmalltowntheearthquakeoccurred.A.where,whichB.which,whereC.which,thatD.that,where30.——Fewchildrenareasbrightasheis,andalso,heworksveryhard.——It'snothathealwaysgetsthefirstplaceinanyexamination.A.question B.doubt C.problem D.wonder答案与提示：.Cit在此句中是形式主语，真正的主语是that从句。这个句型的结构是：itbe+过去分词+that从句。.Dittakessb.sometimetodosth.意为“花费时间做某事”。It是形式主语，代替不定式短语。此句是将来时态。3.D本题用的是therebe句型。Thereisnoneedto...是这个句型的一种表达方式，意思是“没有必要.一”。4.DIhadexpected的宾语是前面所提到的play。英语中，通常用it和one来替代前面单数名词，可以选C或D，one所代替的是同类事物中“一个”，而it所代替的是前面提到过的同一事物，所以答案为D。5.Atomasteraforeignlanguagewithoutmuchmemorywork是动词不定式短语作think的宾语。当句子的宾语是动词不定式或that从句时，我们通常用it作形式宾语，但是如果宾语不与形容词在一起，一般不能用it作形式宾语。6.B本题是一般疑问句。matter（有关系，要紧）经常用于否定句和疑问句，常用句型是：Doesitmatter…？Itdoesn'tmatter…。7.C不定代词one常用来代替与前面已提到的一个事物（人或东西），以避免重复。one表示同类事物中的“任一个”，即：表示泛指，而theone则表示确指。人称代词it被用来代替前面提到的那个东西。不定代词each常表示“每一个”的意思。根据题意（你要用我的尺子吗？不，谢^谢。我自己有一支。）和结构，应选C。 8.A不定代词one和theone都可以被用来代替前面提到过的一个同类事物（人或东西），以避免重复。one表示泛指，而theone表示确指。题意为：“你指的是哪个人？”“那位戴一只新金表的。"9.AItis/hasbeen...since...did...（时间状语从句） 意思为：自从...以来已有