高中英语语法-it的用法

5.---Where is my book ?---It’s on the table.
6.---Whose exercise-book is that? It’s hers.
7.---Who is making such a noise?
--- It must be the children.
8. It’s kind of you to help me with the problem. 9. I think it hard for you to do the task on your own. 10. It was because he was ill that he didn’t come to school yesterday. 11.It is high time (that ) she wrote a letter to her boyfriend .
观察并思考：it 在下列句中的意义和作用。 p292 1. It was very quiet at the moment .
2. It is eight o’clock .
3. It is five kilometers from the office to my home. 4. It was rainy in spring in China.
强调句型的两种变形形式： 一般疑问句形式：Is/ Was it … that…? 特殊疑问句形式： Who/ Whom /When/ Leabharlann Baiduhen 等 + is/ was it that …?
• it用于下列常见的句型中:
It seems/happens/appears (to sb)+ that clause如：好象……
用于此结构的动词有：consider, think, make, feel, find, believe, count, declare, deem(认为,相信), fancy, feel, guess, imagine, judge, prove, regard, see, show, suppose, think, understand, take等。
• It is time (for sb.) to do sth. • It is (high) time that sb. did sth.(虚拟语气) 是某人该做……的时候了 It is high time that Rober went to school.
• It is /was/will be the first/second/third … time that … 这是某人第几次做…… • It is the first time that I have been here. • It was the second time that he had seen the film.
• • • • • •
• • • •
The use of “it” Teaching aims: Help the students to master the use of “it” Teaching import points: The usage of “it” used in the subjects position to stand for the infinitive or a clause. The usage of “it” used to talk about time, date, distance or weather. The structure: It is/was + n/adj. + infinitive/clause. It is … that …. Teaching difficulties: How to use the sentence pattern:” It is … that ….” When we emphasized the noun which mean places or time.
4.代替上文中提到过的人或事物。
John hates cats, and it is difficult to say why. • I tried to run away from the police, but it is impossible. The train has arrived. It arrived half an hour ago.
3. 强调结构
It is / was + 被强调部分（主语，宾 语，状语）+ that (被强调为人时用 who / whom) + 句子的其余部分.
• I saw John in the street this morning It was I who / that saw John in the street this morning.（强调主语） • It was John that / whom I saw in the street this morning.（强调宾语） • It was in the street that I saw John this morning. （强调地点状语） • It was this morning that I saw John in the street. （强调时间状语）
---He didn’t go to bed until his father came back last night. It was not until ---___________his father came back that ______he went to bed last night.
It作代词
1. 代替指示代词this，that； What is this? It’s a pen.
2．表示时间，日期，季节，天气，光线明暗，温度，距 离，环境等； It was very noisy (quiet) at the moment.
—What time is it?
—It‟s eight o‟clock.
• （当时我突然想起来我本来和她在当天晚 上有约会。）
It is reported/said/thought/hoped/believed/ + that-clause. • 据报道/据说/人们认为/人们希望/人们相信…… 如： • It is said that the news had reached every part of the world. 据说这个消息传到世界的各个角落。
2）代替动名词或动名词短语成为句 子的形式宾语。
Don't you find it a waste of time watching television too much? She found it troublesome having to go through all the pages of the thick book.
It's very important for us to learn English well.
b)用 of表示人的性格特征或 特点,如：nice (cruel, kind, rude, wise, stupid, clever, foolish, polite…) eg: It is silly of him to say that.
It often rains in summer here. It is a long way to the school.
3．指代人时，一般用于小孩或身份
不十分明朗的人。
1)－Who is the baby? －It„s my teacher‟s son． 2)－Who is that gentleman? －It„s my friend,Tom． 3) —Who is knocking at the door? —It‟s me.
• It looks/seems as if + clause 看 上去好象……
•
It seems as if they had never seen each other before.看上去他们好象从没 见过。 • It looks as if it‟s going to rain.看上去 天要下雨。
3）代替从句：
Didn’t I make it clear to you that I was not coming? I found it very interesting to study English. I thought it strange that Jack should have had so much money to spend these days.
it作引导词 1 形式主语 a) 代替由不定式表示的真正主语 b) 代替由动名词表示的真正主语 c) 代替由从句表示的真正主语
2. it 做形式宾语 a) 代替由不定式表示的真正宾语 b) 代替由动名词或名词短语表示 的真正宾语 c) 代替由从句表示的真正宾语
3. 强调结构
4.补充：有关it的常用句型
• Does it matter if + clause? ……要
紧吗？ • It doesn‟t matter (much) whether/if-clause ……没有（多大） 关系/都一样
• Does it matter if an engineer is a man or a woman?工程师是男人还是女人有关 系吗？
It作代词
it 作引导词
1). 代替由不定式表示的真正主语 It is + adj. / n. + for/of sb.+ to do a)用for形容词通常是表示事物的特 点 或 特 征 , 如 ： important (necessary, possible, impossible, easy, hard, difficult…) eg: It’s difficult for me to learn cooking.
unitl引导的时间状语短语或从句用于否定句 时，也可强调，不过要把not与until放在一起。
Was ______ that I saw last night at the concert? A. it you B. not you C. you D. that yourself Who was it that you met in the street yesterday? 昨 天你在街上遇到的是谁？ Where was it that you met Jack yesterday? 你昨天是 在哪里遇到杰克的？
• • • • • 例：It happened that I was there then. （碰巧当时我也在场。） 例：It appears that he'll be elected. （他像是会当选的样子。） 例：It occurred to me then that I had an appointment with her that evening.
2. 形式宾语
1）代替不定式作为形式宾语： 主语 + v. + it+ 宾补 + to do sth. 如：I think it best to get along well with
people around you. I consider it wrong to cheat in an examination.
3）代替从句
• It is surprising that she should have married a farmer. • It is a well-known fact that smoking can cause cancer. • It is well known to all that the earth is round.
2）可代替动名词表示的真正主语。
常用以下结构:
It+be+fun/a waste of time/no good/no use doing sth
It’s no use going there so early. • It's no good taking in much fat and sugar. • It’s no fun watching the same movie for a second time.