2021届高考二轮复习英语语法专题：-It用法-学案.doc

1、It 用法及其句型 人称代词it是第三人称单数主格或宾格，它可以是在句中充当主语、宾语或表语等， 还可以在句中代替动词不定式、动名词或从句等， 充当形式主语和形式宾语。一It 作人称代词代替前面（或后面）的单数名词或分句所表示的事物。You may borrow the magazine in the school library and keep it for two weeks.Toms mother kept asking him that he should work hard, but it didnt help.在特定的语境中，it 也可以指人，如婴儿，性别不详或身份不明的人等。W

2、hen a baby is crying, it may be hungry.it 起指示代词的作用，表明某人或某物的身份。-Whos dancing over there?-Its my sister.用来指代指示代词 this或that。- Whats this?-Its a keyboard.二 无人称代词it的用法It没有明确的指代，但是说话双方都 明白的情况。 - How is it going at work these days？ Still enjoying it？- Well, just fine.It用来表示时间、天气、季节、距离、环境状态以及度量衡等。Its about

3、ten kilometers from here to the airport.Its cold and windy outside.Its seven oclock.Its summer now and it becomes hotter and hotter.三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。 代替不定式It +be +adj. + (for sb.) +to do sth.It is illegal (for a teenager) to drive a car without a license.It +be +

4、adj. +of sb. to do sth.Its kind of you to help me with the problem.It +takes +sb. to do(=sb takesto do)某人用多长时间做某事It took the men a week to mend our roof. (= The men took a week to mend our roof.) 代替动名词Its no good/use doing Its no use crying over spilt milk.Its (well) worth doingIts (well) worth read

5、ing the book.代替从句It is + noun +从句 It is no secret that the president wants to have a second term at office.It is adj. +clauseIts important that you should apologize to her for your rudeness.It is v-ed +that (should) (verb=demand, request, require, order, suggest, advise, recommend It is +v-ed that=s

6、b /sth is to do (verb=say, report, think, believe, hope, expect, agree, accept, decide, determine, intend, plan, understand, know） It is suggested that they should begin with the third question.It is said that the couple have gotten divorced. (=The couple are said to have gotten divorced.)It +verb +

7、(to sb.) that= sb / sth verb to do (verb = appear, seem, come about, emerge, follow, chance, happen, occur, transpire, turn out , work out) It (so) happened/chanced that they were out. (= They happened/chanced to be out.)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。 verb+ it+ adj./noun (f

8、or/of) to do/clause (verb =think, believe, suppose, consider, feel, make, keep) I think it hard for you to do the task on your own. /I think it hard that youll do the task on your own.Verb + it + adj./noun (ones) doing (adj.=useless/worth/worthwhile)(noun=no use/no good/worth ones while/a waste of t

9、ime/money/energy/words) (verb=think, believe, suppose, consider, feel, make, keep) Ill make it worth your while telling me about his secret.verb + it+ as+ noun/adj.+ clause (verb=accept, regard, take, see, view) The lecturer takes it as encouraging when so many students attend his lecture.v. +it + p

10、rep. + that owe it to sb. that把归功于 leave it to sb that把留给某人去做 take it for granted that 想当然 keep it in mind that Dont bother to arrange anything. Just leave it to me to sort out.It用在不能直接跟宾语从句的动词后面，尤其是表示好恶的动词后，enjoy, like, love, dislike, appreciate, hate, dont mind, be fond of, feel like, see to 宾语从句紧

11、跟it之后 I hate it you can swim so well and I cant.五强调句型 It is/was+被强调部分+ that(who) 强调句型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。 注意谓语动词的人称和数的一致性It is Mary and Tom who often do good deeds.It is I who am going to Beijing next month.在强调时间，地点，原因或方式状语时，要用that而不用 when, where, why, 或howIt was because he was ill th

12、at he didnt come to school yesterday. 在强调not until结构时必须把not与until一起放到被强调的位置上。It is/ was not untilthat that 从句中谓语动词要用肯定式It was not until she took off her dark glasses that I realized she was my brother.特殊疑问句只有疑问词可以被强调，其句型是：疑问词+is/was +it +that从句When was it that he changed his mind to take part in the

13、 activity？强调句型的反意疑问句，其问句部分用isnt/wasnt.It was at eleven last night that I heard a terrible noise from the apartment, wasnt it?若强调句在复合句中作宾语，则强调句必须用陈述语气。I really didnt know where it was that the old man lost his purse.六It引起的几个易混时间句型Its time + 介词短语 + to do / that 从句(that 从句中的谓语动词须用虚拟语气)Its time for us t

14、o have breakfast.Its time that I picked my son from school.It / this / that + is /was/will be + the first(second) time + that 从句 (that 从句中一般使用完成时态)This is the first time that he has visited China.It was / will be long (hours, days, years, etc.) + before 从句It will be two years before we meet again.It

15、 was a long time before I got to sleep last night.It is / had been + 一段时间 + since 从句Its two years since Tom joined the army.Its two years since Tom was in our class.It is /was + 具体时间+ when 从句Its 7 oclock when I get home from work every day.Its at 7 oclock every day that I get home from work.七 强调句与主语

16、从句，定语从句及状语从句的辨析强调句将句子中的it is / was that同时省去，句子仍然成立；而主语从句将that与后面部分代替it，成立。It is Li Leis brother that you met in the street yesterday.It is exciting that we have succeeded in sending up Shenzhou V1.在It is / was. that.的结构中，如从句为定语从句，则句首的it是指示代词，担任主句的主语，that担任从句的主语或宾语，作宾语时可以省略；如为强调句型，则it和that都是引导词，本身无意义

17、，that不充当句子成分，不能省略2. 定语从句的先行词通常是名词、代词或名词短语，而强调句型中被强调的部分可以是名词、副词、介词短语和从句。It is an English book (that / which) I bought yesterday.It was the English book that I bought yesterday.It was a room where we used to have meetings.It was in the room that we used to have meetings.It is a day when the people cel

18、ebrate their victory.It was on that day that people celebrated their victory.1. 状语从句句首的It本身就是句子的主语；而强调句首的It不作任何成分也没有实际意义。2. 状语从句的连接副词that及句子前面的It be不能去掉3. 状语从句的引导词可以是when / where，而强调句型中的that不能用其他词代替。It is such an interesting book that we all like it very much.It is such an interesting book that we a

19、ll like very much.It is such an interesting book as we all like very much.（定语从句）It was already morning when he woke up.It was the next morning that he woke up.八It 常用的固定搭配make it(1).在口语当中相当于succeed,表示：成功、做到、说定、赶上、及时到达 (2).在口语中相当于fix the date for,表示“约定好时间” Its hard to make it to the top in show busine

20、ss. Shall we meet next week? OK. We just make it next Saturday.as it is1).相当于in fact, in reality表示“事实上，实际情况是” (2).相当于方式状语从句，表示“照原样” We had planed to finish the task today, but as it is we probably wont finish it until next week. Leave the table as it is.thats it(1). 相当于Thats all. Thats so much. 表示“至

21、此为止，没有别的了” (2). 相当于 Thats right.表示“对啦” You can have one more sweet, and thats it. I guess the key to the problem is the choice “A” Thats it. catch it在口语中，相当于be punished/scolded for doing sth. wrong. 表示“因做错事而挨骂，受责备，受批评，受惩罚”Well really catch it form our teacher if were late for class again.have it(1).

22、相当于say, insist表示“说，主张，表明，硬说” (2).相当于get to know something,表示“了解，知道，获悉” Rumour has it that they are getting divorced. I had it from John that she was going abroad.Take it/things easy. 相当于Dont worry or dont hurry. 用来劝告别人，表示“不要慌，别担心，存住气”Take it easy! He will do it well.worth it 在口语中，相当于useful, 表示“有好处，值

23、得做”Dont hesitate about it! Its worth it.Believe it or not. 表示“信不信由你”Believe it or not, Tom is getting married to Mary next Sunday.Take it or leave it. v. 要么接受要么放弃That is my last offer. You can take it or leave it.It all depends/that all depends 在口语中，相当于it hasnt been decided yet, 表示“那得看情况，还没有定下来”Are you going to the countryside for holiday? It/That all depends.Its up to sb. 在口语中，相当于its decided by sb. 表示“由决定，由负责，取决于”Shall we go out for dinner? Its up to you.