grammar---it用法

单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Discovering“It”,It,rains cats and dogs.,2.,It,is 20 kilometers from Granddads house to James.,3.,It,is February 10,2014.,4.,It,is 9 oclock at night.,5.,It,is a baby.,6.My mother gave me a book and I like,it,very much.,7.-What is this?-,It,is a book.,天气,距离,日期,时间,性别不明的人,前文提到的事物,Summary,-1)it,用作代词,1.,作非人称代词：常用于指代天气、时间、日期、距离、价值、度量、温度、环境等；,2.,作人称代词：代替,前文提到的事物,、性别不明或被认为不重要的人或物，未指明但谈话双方都明白的事情或情况。,3.,替代,this/that,I have lost my umbrella;Im looking for,it,.,I have lost my umbrella;I think I must buy,one,.,The umbrella you bought is cheaper than,that,I bought.,it，one，that 作替代词的区别,同名同物,同名异物,同名异物,A chair made of steel is stronger than,one,made of wood.,The water in the cup is hotter than,that,in the pot.,one,为泛指,既可以替代人，也可以替代物，相当于,a,an,单数可数名词；复数用,ones,。,one,前有形容词时，其前需加,a/an,。,that,为特指,只能替代物，相当于,the,单数可数名词或不可数名词。复数用,those,。,that,可以根据语义在它的后面加上一些定语，多数是,of,短语；它的前面不能存在任何定语。,1.We need a new cupboard for the kitchen.So Peter made _ from some wood we had.A.it B.one C.himself D.another,2.-Have you heard the latest news?,-No,what _?,（宁夏,2007,）,A.is it B.is there C.are they D.are those,3.To her joy,Della earned first the trust of her students and then _ of her colleagues.(,辽宁,2013),A.that B.one C.ones D.those,It,is amazing that at my age I am still fit.,2.,It,is easier to fall than to rise.,3.,It,is no use crying over spilt milk.,形式主语,真正的主语,2）it作形式主语,遵循英语语言的尾重原则,避免句子头重脚轻。,it作形式主语的几种常见句型：,Its+adj.+of/for sb.,to do,sth,It is no use/no good/useless/senseless/dangerous/enjoyable/worthwhile/a waste/fun+,doing,sth,adj,可修饰人,adj,不可修饰人,It is+adj./n./,过去分词,+that,从句,important,necessary,clear,possible,a pity,a shame,no wonder,a fact,said,reported,believed,suggested,1.Most people believe smoking causes cancer.,It,is believed _,2.Dont try to quit on a stressful day.,It,is no use _,trying to quit on a stressful day.,that smoking causes cancer.,3.China produces one third of the worlds,cigarettes.,It,is a fact _,_,4.You are not allowed to advertise,cigarettes in this country.,It,is illegal _,_,that China produces one-third of the worlds cigarettes.,to advertise cigarettes in this country.,1.I think,it,best that you should do more,exercise.,2.He found,it,difficult to accustom himself,to getting up early.,3.,I think,it,no use arguing with him.,3）it作形式宾语,v.+it+adj./n.+that,从句,/to do/doing,find,think,feel,believe,consider,make,etc.,.(05全国),The chairman thought _ necessary to invite Mr.Obama to visit Peking.,A.that B.it C.this D.him,The chairman thought,it,was necessary to invite Mr.Obama to visit Peking.,2.,动词,+it+to sb.+that,oweittosb.that,把,归功于,leaveittosbthat,把,留给某人去做,takeitforgrantedthat,认为,理所当,然,keepitinmindthat,把,记在心里,He took it for granted that his girlfriend would come back again.,3.,动词（短语）,+it+that/when/if,常用在该句型中的动词（短语）有：,enjoy,like,love,dislike,appreciate,hate,prefer,answer for,（对,负责）,seeto,（确保，务必）,depend on,insist on,Ihateitwhen the weather is cold in winter.,It is(high)time,that,“,是（正是）,的时侯了,从句的时态：,过去时。,用,should+,动词原形，,should,不,能省。,孩子们该睡觉了。,It is time that children should go to bed.,=It is time that children went to bed.,含,有,it,的句型,2.It is/was the first(second.)time that.,从句的时态：前面是,is,从句用现在完成时,(have/has done),前面是,was,从句用过去完成时,(had done),It is the first time I have been here.This was the first time I had been here.,含有it的句型,3.It is/has been+,时间段,+since.,since,引导的从句通常是一般过去时态，而且是瞬间动词。,“自从,已,经多久了”,It is(has been)5 years since his father died.,4.It was/will be+,时间段,+before.,before,从句中常是一般时或过去时两种时态,It was 3 days before he went to Beijing.It will be not long before he finishes his job.,含有it的句型,5.It is/was+,时间点,+when.,“,当,的,时,候已经,”,It was 5 oclock when he came here.,例：我们该采取行动了。,Its(high)timethatweshouldtakeaction.,例：这是他第三次没有通过驾照考试。,Itsthethirdtimethathehasfailedthe,drivingtest.,例：不久后他,们到了。,Itwasnotlongbeforetheyarrived.,含有it的句型,1.,基本句型,Itis/was+,被强调部分,+that(who)+,其他成分,用来强调谓语动词以外的任何句子成分。当,被强调部分是人时也可以用,who,。,强调句型,2.,一般疑问句式,Is/Was it+,被强调部分,+that(who)+,其他成分,3.,特殊疑问句式,特殊疑问词,+is/was it+that+,其他成分,It was a new book,he wanted to buy.,It was Tom,I met in the street.,3.It was during the holiday,he got to know that girl.,that,who,that,请与同桌一起把上面三个句子改写为,强调句的一般疑问句式和特殊疑问句式。,It is/was+not until +that.,该句型主要用于强凋时间状语，译成汉语“直到,才,”,。例如,:I didnt realize she was a famous film star until she took off her dark glasses.,It was not until she took off her dark glasses that I realized she was a famous film star.,强调句的,not until,句型,It was _ back home after the experiment.,A.not until midnight did he go,B.until midnight that he didnt go,C.not until midnight that he went,D.until midnight when he didnt go,1.,在,强调句型中考查主谓一致,It was not luck but difficulties that,him success.,A.makes B.make,I think it is the sales manager,rather than the sales girl,who,to blame.,A.is B.are,2.,强调句型中的,be,动,词可与,情态动,词相结,合,It might have been John,bought it for Mary yesterday.,What B.since C.that D.when,It may be next week,she leaves for London.,A.what B.since C.that D.when,3.,强调句型中含有名词性,从句,I have forgotten,you put the,dictionary.,that it was there,B.where was it