“It”用法及其句型和固定搭配讲解"It"用法及其句型和固定搭配，是高中英语语法的重点、难点，又是近几年高考的热点，因此应给予充分的重视，现将it用法归纳如下：一、It用作实词表达以下概念:指代前文提到的事物，前文中的this,that；替代前文中的内容；指代一位性别不明的小孩或未知的人；指代未指明但谈话双方都知道的那件事；指代时间、天气、气候、距离等自然现象……二、It用作形式主语替代作主语的从句、动词不定式、动名词，而把真正作主语的从句、动词不定式、动名词置于句尾。It作形式主语的常见句型：1.代作主语的动词不定式，其句型为(1)Itbeadj.(forsb.)todosth.此处adj.通常为描述事件的形容词：easy,difficult,hard,necessary,unnecessary,possible,impossible,likely,unlikely,right,wrong,important,unimportant,legal,illegal,well-mannered,ill-mannered,polite,impolite,clear,obvious,certain,suitable,proper,fit,useful,useless,dangerous…例Itisillegal(forateenager)todriveacarwithoutalicense.(2)Itbeadj.ofsb.todosth.此处adj.通常为描述人的形容词：kind,unkind,nice,rude,cruel,considerate,thoughtful,thoughtless,careful,careless,silly,foolish,stupid,clever,wise,crazy.例It'skindofyoutohelpmewiththeproblem.(3)It替代作主语的动名词的常见句型It'snogood/usedoing…It's(well)worthdoing…It's(well)worthone'swhiledoing/todo…It's(well)worthwhiledoing/todo例It'snousecryingoverspiltmilk.2.It替代作主语的从句常见句型(1)Itis+noun+从句例Itisnosecretthatthepresidentwantstohaveasecondtermatoffice.(2)Itisadj.+clauseIt'ssurprisingthat…(should)………竟然……It'sapity/shamethat…(should)………竟然……例It'simportantthatyoushouldapologizetoherforyourrudeness.(=It'sofmuchimportancethatyoushouldapologizetoherforyourrudeness.)(3)Itverbsb.+clause=Itisv-ing+clauseIt+surprise/delight/interest/disappoint/worry/disturb/annoy/amaze/bother/concern/frighten/please/angersb.that…例Itworriedmethatshedrovesofast.(=Itwasworryingthatshedrovesofast.)(4)Itverb(tosb.)that…=sb/sthverbtodo(verb=appear,seem,comeabout,emerge,follow,chance,happen,occur,transpire,turnout,workout)例It(so)happened/chancedthattheywereout.(=Theyhappened/chancedtobeout.)(5)Itisv-edthat…=sb/sthistodo(verb=say,report,think,believe,hope,expect,agree,accept,decide,determine,intend,plan,understand,know）例Itissaidthatthecouplehavegottendivorced.(=Thecouplearesaidtohavegottendivorced.)(6)Itisv-edthat…(should)…(verb=demand,request,require,order,suggest,advise,recommend例Itissuggestedthattheyshouldbeginwiththethirdquestion.三、It作主语的句型1.Ittakessb.…todo…(=sbtakes…todo…)某人用多长时间做某事例Ittookthemenaweektomendourroof.(=Thementookaweektomendourroof.)2.It's(just)(un)likesb.todo…（不）像某人做某事的风格例Itwas(just)likehimtothinkofhelpingus.3.It's(about/high)timethat…should/v-ed…是该做某事的时候了例It's(about/high)timethatweshouldtakeaction.4.It'sthex-thtime(that)…havev-ed…第几次做某事了例It'sthethirdtimethathehasfailedthedrivingtest.5.Itis/hasbeen…since…continuousv-ed(延续性动词)某动作已有多长时间不发生了例It's10yearsthathelivedhere6.Itwas(not)…before…过(不)了多长时间某动作发生了例Itwasnotlongbeforetheyarrived.四、It作形式宾语用来替代作宾语的从句、动词不定式、动名词，而把真正作宾语的从句、动词不定式、动名词置于句尾。It作形式宾语的常见句型：1.verb+it+adj./noun(for/of)todo/clause(verb=think,believe,suppose,consider,feel,make,keep…)例Ithinkithardforyoutodothetaskonyourown./Ithinkithardthatyou'lldothetaskonyourown.2.verb+it+adj./noun(one's)doing(adj.=useless/worth/worthwhile)(...
