高三英语the usage of it课件.ppt

theusageofit it作为人称代词 用来表示动物或无生命的物体等 it在句中可表示 时间 距离 自然现象 等 it还可引导一些固定句型 it在句子中可充当形式主语 宾语等 一 it作为人称代词 it可以指代前面提到的事物 动物 植物及无生命的东西 1 lookatthebird italwayscomestomywindow 2 iplantedatreelastyearanditisabouttwometershigh 3 heisweakatgrammarandherealizedit it可以指上文提到的整个事情 well youmustn tplayontheroad it sverydangerous 3 可以指代人 1 指代心目中不太清楚的人 常在打电话或敲门时用 whoisknockingatthedoor it sme 2 指代心目中指的人 look someoneiscoming whocanitbe 3 指代性别不详的婴幼儿 lookatthelittlebaby it ssosmall 4 在问句中有指示代词作主语时 回答常用it指人 who sthat isithelen yes you reright it shelen 二 it作为无人称代词指时间 距离 自然现象及环境 形势等 1 it seighto clockinthemorning it swinternow theweatheriscold 2 it sonlyfiveminutes walkfromhere 3 itisgoingtorain 4 ifit sconvenient icanseeyoutomorrow 1 itistime forsthit stimeforharvest forsb todosthit stimeforustogotobed that从句it stimethatwewenttobed 2 itis wasthefirst second timethat从句1 itisthefourthtimethathehasattemptedtoescape 2 itwasthesecondtimethatihadvisitedbeijinglastyear 3 it be is was hasbeen 时间段 since从句1 itis hasbeenfiveyearssinceibegantostudyenglish 2 itwastwoyearssincesheleftschool 4 it be was willbe 时间段 before从句 过多久后才 1 it llbehalfayearbeforeiseeyouagain 2 itwastwomonthsbeforeireturnedschool it指时间的其他用法 三 it可以用作形式主语 常见的句型有 itis was 形容词 forsb todosth itisn teasyforsomesmokertoquitsmoking itis was 形容词 ofsbtodosth it skindofyoutohelpmetodoit it 系动词 形容词 todosth itseemedimpossibleforhertofinishtheworkbeforesix itis was 形容词 名词 doingsth 1 it sawasteoftimewaitinghere 2 it snouse goodwaitinghere itis was 形容词 从句 itisclear plaintruecertainsureobvious that从句 陈述语气 itisimportant necessary that从句 虚拟语气 1 itisamazingthatatmyageiamstillfitenoughtocycle20kilometresinanafternoon 2 itisimportantthatwe should learnaspecialskill 6 itis was 名词词组 todosthit sapitytomisstheearlybus that从句it sawonderthatyoucouldworkoutthehardproblemonyourown one sturn duty pleasure apity greatfun ahabit time aruler ashame no awonder asuggestion mywish 虚拟语气 7 itis was hasbeen 过去分词 that从句1 ithasbeenfoundthatsomepeoplehavetotryseveraltimesbeforetheyfinallystopsmoking 2 itissuggestedthatsomemeasures should betakentostoppollution 8 ittook takessbsometimetodosth ittakeshimfifteenminutestogotoschooleveryday 9 itcost costssbsomemoneytodosth itcostme100yuantobuythiscoat 10 it 动词 主语从句itdoesn tmatterwhetherhecomesornot 四 it作形式宾语 代替后面的真正宾语 不定式 动名词和从句 常见的句型结构 主语 谓语 it adj n todo doing 从句 常用于此句型的动词有 make think feel find consider等 1 yourmothertoldmethatyouhavestartedsmokingandthatyouarefindingitdifficulttogiveup 2 theymakeitcleartothepublicthattheyaredoinganimportantandnecessaryjob 3 hefeelsithisdutytotakecareofher 五 it可用来引导强调句型 强调句型 itis was 被强调部分 that who 其它成分1 itwasithat whosenttheboytothehospital 2 wasitduringthewarthattheboy sfatherdied 3 whywasitthattheyoungmanwasputintotheprison 六 在短语askfor 请求 dependon 依靠 answerfor 负责 担保 insiston 坚持 seeto 确保 负责 等后接that从句时 必须用形式宾语it 1 shewillanswerforitthathepassestheexam 2 wouldyouseetoitthatthechildrengetgoodrestaftertheexercises 七 某些及物动词如 like love enjoy prefer hate appreciate等之后若没有宾语 而直接跟上if when的从句时 要在从句前加上it 1 iwouldappreciateitifyouhelpmewiththeproblem 2 ilikeitwheretheriverisclearandtheskyisblue 3 ihateitwhensomeoneislaughingandspeakingwithfoodinher hismouth idon tmindhercriticizingme but ishowshedoesitthatiobjectto a itb thatc thisd which worriesmethewayhekeepschanginghismind a thisb thatc whatd itificanhelp idon tlikeworkinglateintothenight a sob thatc itd themitremains