it基本用法复习.ppt

It的用法,It最基本的用法是人称代词，主要代表刚提到的东西以避免重复。,Lookatthatcar.Itsgoingmuchtoofast.Whereisthecarkey?-Iputitinyourdrawer.,也可以代表抽象的东西。,Itsallmyfault.,也可以指动物或未知性别的婴儿。,Whatabeautifulbaby，isitaboy?Howaboutthebaby?-Illtakecareofit.,还可代表一个彼此都知其何所指的东西。,Wheredoesithurt?Ifhedoesntcome,Icanthelpit.Youhavesavedmylife.Ishallneverforgetit.,It可以表示“是谁（在某处或做某事）,“Whosthat?”“Itsme.”Itsyourmotheronthephone.“Why,itsyou!”shecried.,It还可以用来泛指某件事,Isntitawful!Itdoesntmatter.,it有时并不指具体东西，而指天气、时间、环境、距离等，称为非人称代词it.,Itsraining.ItsTuesdaytoday.Itsquiethere.Itstwomilestothebeach.,非人称代词it：It用于代替指示代词：,替代词one,ones,that,those,it,this,that,one,ones,that,those,That替换单数可数名词或不可数名词；one只替换单数的可数名词。,Thevaseontheleftismorebeautifulthantheoneontheright.ThecoffeeproducedinBrazilismorefamousthanthatinMexico.,That只用于替换表示事物的名词，而one/ones替换表示人和表示事物的名词皆可。,Hisyoungersisteristallerthantheelderone.Ineedtheplasticbags,notthepaperones.,ThecomputersinourschoolareconnectedtotheInternetwhilethoseintheirschoolarent.Thefootballplayersonourteamseemtobemoreenergeticthanthoseonyourteam.,That/those一般用于替换有定冠词的名词；one/ones用于替换有不定冠词的名词。,Thestyleofthebuildingissimilartothatofatemple.ACDplayermadeinJapancostsmorethanonemadeinHongKong.,That/those一般不带前置定语，但必须有后置定语。One/ones都可。当替换词的后置定语用所有格的of短语或当替换词被所有格修饰时，不用one/ones而用thatof/thoseof.,Ilikethevasebetterthantheone/thatinanothershop.Thewindowsofyourflatarecleanerthanthoseofmine.Agrandparentsjobiseasierthanthatofaparent.,2)it,this和that,都可以替代前文已提到的事或情况，细微差别在于it不如其余两者那么强调。,Soshedecidedtopaintthedoorpink.Itupsettheneighboursabit.Soshedecidedtopaintthehousepink.Thatreallyupsettheneighbours,asyoucanimagine.,当前面提到的事物不止一件时，it通常指最先提到的事物，而This/that是指最后提到的事物。,Wekeeptheicecreammachineinthespareroom.Itismainlyusedbythechildren.(指themachine)Wekeeptheicecreammachineinthespareroom.This/Thatismainlyusedbythechildren.(指thespareroom),This可以出现在它所指代的事物之前；而that则指上文所提到的事物。,Listentothis!Wewillhavethreedaysoff.“Apennysavedisapennyearned.”Whosaidthat?,3)It和one,It用以指特定的前面提到过的事物，即：it和它替换的是同一个事物，it前无修饰语；而one用于替换与前提事物有共同之处但并不完全一样的事物，因此，one之前或之后一定有修饰语来加以区别。,IboughtadictionarythreeyearsagoandIamstillusingitnow.IboughtadictionarythreeyearsagobutIamgoingtobuyanewonesoon.,形式主语it：有下面几种类型：,be+形容词+不定式eg:Itsbettertobeearly.be+名词+不定式eg:Itwashisdutytotakecareoftheorphans.be+介词短语+不定式eg:Itsbeyondmetosaywhy.It+及物动词+宾语+不定式eg:Itmakesmesicktothinkaboutit.be+名词+动名词eg:Itsnogoodstandinghereinthecold.be+形容词+动名词eg:Itshelplesstryingtoconvinceher.其他结构+动名词eg:Itdoesntmatterwaitingafewmoredays.,用于由that引导的主语从句，有下面几种类型：,it+be+形容词+that从句：eg:Itisnaturalthattheyshouldhavedifferentviews.it+be+名词+that从句:eg:Itsashamethatyouresick.it+动词（+宾语）+that从句eg:Ithappenedthatshewasntinthatday.Eg2:Itneveroccurredtomethatperhapsshewaslying.It+动词的被动语态(said/believed/thought/expected/reported/known+that从句eg:ItssaidthattherehasbeenanearthquakeinIndia.,形式宾语it:,it可以代表不定式：,Shefounditdifficulttoconvincehim.Hefeltithisdutytotakecareofthem.,It代表that引导的从句：,Itookitforgranted(that)youwouldbecoming.,It代表连接代（副）词引导的从句：,Hehasntmadeitclearwhenheiscomingback.Theyhaventmadeitknownwherethemeetingistotakeplace.,用it跟从句用法：,1）it+be+形容词+从句：Itisnotcleartomewhyhebehavedlikethat.2）it+be+名词+从句:Itsapuzzlehowlifebegan.3）it+动词（+宾语）+从句Itdoesntmattermuchwherewelive.Itmakesnodifferencewhetherwegobytrainorbyboat.4）it+动词的被动语态+从句Itisnotdecidedwhowilleditit.,5）it+动词be+that从句No,itcouldntbethattheywereinterestedinhim.6）It+be+一点时间+whenItwasChristmasEvewhenIgotthenewsofhisbeingkilledinacarcrash.7）It+be+一段时间+sinceItis/hasbeenthreeweeksinceIlastheardfromhim.8）Itistimetodo/that(谓语用过去时态）Itistimeforustogivethehouseathoroughcleaning.Itistimethatwegavethehouseathoroughcleaning.,9）It+be+thefirst/secondtimethat(谓语动词用完成时态）ItisthefirsttimeinhistorythattwoNobelPrizeshavebeenawardedtothesameperson.10）Ittakessb.TimetodoIttookMary20minutestochooseasuitabledressfortheparty.,NancysawyoursisterinTokyolastweek.ItwasNancywhosawyoursisterinTokyolastweek.ItwasyoursisterwhomNancysawinTokyolastweek.ItwasinTokyothatNancysawyoursisterlastweek.ItwaslastweekthatNancysawyoursisterinTokyo.,It用于强调句,结构：It+动词be+强调部分+who(whom)/that+其他部分it可以用来对句子的某一成分加以强调。,有些否定句也可以改成这种强调结构：Ididnthearfromheruntillastsummer.ItwasntuntillastsummerthatIheardfromher.Ididntdoallthisformyself.ItwasntformyselfthatIdidallthis.,问句也可变成这种结构：Whocalledhim“comrade”?Whowasitthatcalledhim“comrade”?Howdidyouforgettolockthedoor?Howwasitthatyouforgottolockthedoor?,Ex:把下列句子改为强调句：1.Petersawhisfriendintheparkyesterday.2.Ididntreceivemyletteruntilyesterday?4.Didithappenin1980?5.WhydoeseveryonethinkImnarrow-minded?,1.Petersawhisfriendintheparkyesterday.,ItwasPeterwhosawhisfriendintheparkyesterday.,ItwashisfriendwhomPetersawintheparkyesterday.,ItwasintheparkthatPetersawhisfriendyesterday.,Itwasyesterdayt