it用法大全形式宾语形式主语
It 做形式主语和形式宾语的句型
常见的It句型（包括it做形式主语和形式宾语）1.It is/was + 被强调部分+ that/who ... 该句型是强调句型。
被强调部分可以是主语，宾语，表语或状语。
强调的主语如果是人，that 可以由who 换用。
如果把这种句型结构划掉后，应该是一个完整无缺的句子。
这也是判断强调句型与其它从句的方法。
一般陈述句：Tom bought a book in this bookshop yesterday.It is Tom who/that bought a book in this bookshop yesterday. 强调主语It is a book that Tom bought in this bookshop yesterday. 强调宾语It is in this bookshop that Tom bought a book yesterday. 强调地点状语It is yesterday that Tom bought a book in this bookshop. 强调时间状语2. It is not until + 被强调部分+ that ... 该句型也是强调句型。
主要用于强凋时间状语，译成汉语“直到……才……”，可以说是not ... until ... 的强调形式。
It was not until she took off her dark glasses that I realized she was a famous film star. 强调句= Not until she took off her dark glasses did I realize she was a famous film star. 倒装句= I didn't realize she was a famous film star until she took off her dark glasses. 一般句式3. It is+形容词（clear /obvious/true/possible/certain…）+ that 从句该句型中it 是形式主语，真正的主语是that 引导的主语从句，常译为“清楚（显然，真的，肯定……）”是主语从句最常见的一种结构。
it作形式主语和形式宾语
it作形式主语和形式宾语it既可作人称代词，用来表示动物或无生命的物体等，也可以作无人称代词，在句中作主语，表示“时间”、“距离”、“天气”等。
它还可以引导强调句，使语气得以加强。
此外，it在句中能作引导词，充当句子中的形式上的成分，如形式主语、形式宾语等。
㈠it作形式主语：it作形式主语时没有具体的意义，而只是帮助把真正的主语移到句子后部去，使句子显得平稳一些。
it作形式主语时，可以代替三种形式：不定式、动名词和主语从句。
⒈it代替不定式短语常用于下列句型中：It + be +形容词+ (for/of sb.) to do sth.It + be + 名词+ to do sth.It takes sb. some time to do sth. 干…花了某人…时间It’s up to sb. to do sth. 干…是某人的职责或义务如：①It is everyone’s duty to obey the law.遵守法律是每个人的义务。
（it作形式主语, 代替不定式短语to obey the law）②It is difficult for a foreigner to learn Chinese.对于一个外国人来说，学习汉语是困难的。
（it作形式主语, 代替不定式短语to learn Chinese）③It is not right to use these places as rubbish dumps.把这些地方用来倒垃圾是不对的。
（it作形式主语, 代替不定式短语to use these places as rubbish dumps）④It took them a year to build the bridge.建这座桥花了他们一年的时间。
（it作形式主语, 代替不定式短语to build the bridge）⑤It is bad manners to stare at people.瞪着眼睛看人是不礼貌的。
it用法大全形式宾语形式主语
2.非人称代词it
it有时并不指详细旳东西，而泛指天气、时间、环境等， 称为非人称旳it： 2.1.指天气： It is a lovely day, isn’t it? It is a bit windy.
2.2.指时间: It was nearly midnight when she came back.
用It作形式主语旳句型： (1) It is adj.＋ to do sth. It is difficult to translate this article.翻译这篇文章 极难。
(2) It is adj. ＋ for/of sb.＋ to do sth. It is important for us to learn English.学习英语对我 们很主要。
㈠ 1.it作人称代词
1.1.it旳最基本使用方法是作人称代词，主要指刚 提到 旳事物，以防止反复:
Ningbo is a beautiful city, isn’t it?
1.2.也能够指动物或婴儿(未知性别旳婴儿或孩子): Is this your dog？No, it isn’t.
1.3.也可指抽象事物: It was a great surprise to me when he did a thing like that．
2）.It is +v-ed +that 从句 ① It is said (reported， learned....) that ...
据说（据报道，据悉．．．）“。 It is said that he has come to Beijing.
= He is said to have come to Beijing.
②不论被强调部分是哪种状语，只能用 that连接，不得使用where、when等连词.
“It”作形式主语和形式宾语的用法详解
it作形式主语和形式宾语it既可作人称代词，用来表示动物或无生命的物体等，也可以作无人称代词，在句中作主语，表示“时间”、“距离”、“天气”等。
它还可以引导强调句，使语气得以加强。
此外，it在句中能作引导词，充当句子中的形式上的成分，如形式主语、形式宾语等。
㈠it作形式主语：it作形式主语时没有具体的意义，而只是帮助把真正的主语移到句子后部去，使句子显得平稳一些。
it作形式主语时，可以代替三种形式：不定式、动名词和主语从句。
1. it代替不定式短语常用于下列句型中：It + be +形容词+ (for/of sb.) to do sth.It + be + 名词+ to do sth.It takes sb. some time to do sth. 干…花了某人…时间It’s up to sb. to do sth. 干…是某人的职责或义务如：①It is everyone’s duty to obey the law.遵守法律是每个人的义务。
（it作形式主语, 代替不定式短语to obey the law）②It is difficult for a foreigner to learn Chinese.对于一个外国人来说，学习汉语是困难的。
（it作形式主语, 代替不定式短语to learn Chinese）③It is not right to use these places as rubbish dumps.把这些地方用来倒垃圾是不对的。
（it作形式主语, 代替不定式短语to use these places as rubbish dumps）④It took them a year to build the bridge.建这座桥花了他们一年的时间。
（it作形式主语, 代替不定式短语to build the bridge）⑤It is bad manners to stare at people.瞪着眼睛看人是不礼貌的。
it作形式主、宾语的用法解析
it作形式主、宾语的用法解析it作形式主、宾语的用法解析IT这个词中英语中最渐渐不过了，当it作为形式主语和形式宾语出现时，你会用法吗?以下是店铺整理的it作形式主语和形式宾语的用法解析，希望对你有所帮助。
It 用作形式主语当不定式(短语)、动名词(短语)或从句在某个句子中作主语时，为保持句子结构前后平衡，避免头重脚轻，因此常用it 作形式主语置于句首，而将真正的主语放在句尾。
此时it只起先行引导作用 ...一、 It 用作形式主语当不定式(短语)、动名词(短语)或从句在某个句子中作主语时，为保持句子结构前后平衡，避免头重脚轻，因此常用it作形式主语置于句首，而将真正的主语放在句尾。
此时it只起先行引导作用，本身无词义。
e.g. It is wrong to tell a lie.(说谎是错误的。
) 〔It为to tell a lie的形式主语〕It is no use arguing about it.(争吵是没用的。
) 〔It为arguing about it的形式主语〕It is uncertain who will come.(谁要来还不确定。
) 〔It为who will come的形式主语〕It 作形式主语的.常见句型：① It + be + 形容词+ to do sth. / doing / that ….e.g. It is very important to learn a foreign language.(学一门外语非常重要。
)It is useless crying over the spilt milk.(覆水难收。
)It was really surprising that she married a man like that.(她嫁给那样的男士真让人惊讶。
)② It + be +名词词组+ doing / that ….e.g. It is no good telling lies.(撒谎没好处。
it做形式宾语的五种形式
it做形式宾语的五种形式
it做形式宾语的五种形式如下：
1、主语+think+形式宾语it+形容词/名词+to do sth.
2、主语+believe+形式宾语it+形容词/名词+to do sth.
3、主语+make+形式宾语it+形容词/名词+to do sth.
4、主语+find+形式宾语it+形容词/名词+to do sth.
5、主语+consider+形式宾语it+形容词/名词+to do sth.
形式宾语介绍：
当不定式（短语）、动名词（短语）或从句在某个句子中作宾语时，为保持句子结构平衡，避免句式结构的混乱，常用it作形式宾语，而将真正的宾语放在句尾。
此时it仍只起先行引导作用，本身无词义。
特殊形式宾语：
通常意义的形式宾语主要见于真正宾语为不定式、动名词、从句等且其后跟有宾语补足语时的情形，即用于“动词+it+宾语补足语+真正的宾语”这样的结构，但以下几类形式宾语却比较特殊，其后没有宾语补足语。
宾语介绍：
宾语，也称受词，是指一个动作（动词）的接受者。
宾语分为直接宾语和间接宾语两大类，其中直接宾语指动作的直接对象，间接宾语说明动作的非直接，但受动作影响的对象。
一般而言，及物动词后面最少要有一个宾语，而该宾语通常为直接宾语，有些及物动词要求两个宾语，则这两个宾语通常一个为直接宾语，另一个为间接宾语。
在英语中，有些动词接了一个宾语后句子意思仍不完整，还需要再加上一个词或短语放在宾语之后来补充说明其身份、特征、状态或所做的动作，这种“宾语+宾语补足语”结构称为复合宾语。
it 作形式主语、形式宾语、it开头的短语
It + take ( sb. )+ 时间（金钱）+ 动词不定式
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练习题
B 1.(1)______ is known to us all is that English is a useful language. D (2)______ is known to us all, English is a useful language. A (3)_____ is known to us all that English is a useful language. A. It B. What C. That D. As
• 从句谓语要用一般过去时，也可用should do
• It is high time that I went to see my mother in the hospital. • It is time for you to do your homework.
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以it开头的句型 5. it is/was +强调内容 + that/who从句
• It’s a waste of time talking to her any more. • It is no use arguing about the matter with him.
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It 作形式主语 • 9. It + take ( sb. )+ 时间（金钱）+ 动词不定式
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It的用法及句型总结
It的用法及句型总结"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，如前文中的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) It be adj. (for sb.) to do sth.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: It is illegal (for a teenager) to drive a car without a license.(2) It be adj. of sb. to do sth.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's kind of you to help me with the problem.(3) It替代作主语的动名词的常见句型:It's no good/use doing…It's (well)worth doing…It's (well)worth on e's while doing/to do…It's (well)worth while doing/ to do例: It's no use crying over spilt milk（覆水难收）.2. It替代作主语的从句常见句型：(1) It is + noun +从句例: It is no secret that the president wants to have a second term at office.(2) It is adj. +clauseIt's surprising that… (should)………竟然……It's a pity/shame that…(should)………竟然……例: It's important that you should apologize to her for your rudeness.(=It's of much importance that you should apologize to her for your rudeness.)(3) It verb sb. + clause= It is v-ing + clauseIt+surprise/delight/interest/disappoint/worry/disturb/annoy/amaze /bother/conc ern/frighten/please/anger sb. that…例: It worried me that she drove so fast.(= It was worrying that she drove so fast.)(4) It verb (to sb.) that…= sb/sth verb to do例: It (so) happened/chanced that they were out.(= They happened/chanced to be out.)(5) It is v-ed that…=sb/sth is to do(verb=say, report, think, believe, hope, expect, agree, accept, decide, determine, intend, plan, understand, know）例: It is said that the couple have gotten divorced.(=The couple are said to have gotten divorced.)(6) It is v-ed that … (should)…(verb=demand, request, require, order, suggest, advise, recommend例 It is suggested that they should begin with the third question.三、It作主语的句型1. It takes sb. … to do…(=sb takes…to do…)某人用多长时间做某事例: It took the men a week to mend our roof.(= The men took a week to mend our roof.)2. It's (just)(un)like sb. to do…（不）像某人做某事的风格例: It was (just) like him to think of helping us.3. It's (about/high) time that… should /v-ed…是该做某事的时候了例: It's(about/high) time that we should take action.4. It's the x-th time (that) … have v-ed…第几次做某事了例: It's the third time that he has failed the driving test.5. It is/has been… since …continuous v-ed(延续性动词) 某动作持续了多长时间例: It's 10 years since he lived here6. It was(not)… before…过(不)了多长时间某动作发生了例: It was not long before they arrived.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作形式主语和形式宾语
It作形式宾语
1. find
consider
think
believe
+ it + adj./ n. + for sb. to do sth.
that 从句
feel
make
People felt it impossible for man to fly into outer space some years ago.
8. 他竟然那样举止不当, 似乎很奇怪. It seemed strange that he should have behaved like that. 9. 那天晚上他恰巧在那里.
It happened that he was there that evening.
10. 谁赢得这次竞选和我关系不大. It’ll make no difference to me who will win the election. 11. 他是否来都没关系.
I consider it a shame that we have lost the game.
用以上2个句型造句. 1.我认为他几乎每晚都出去散步是很奇怪的. I think it very strange that he goes out walking almost every night.
that 从句
It seems wise for us not to expect too much of him. It appears all right to tell him everything about it.
It seems true that he will take the place of Mr. Li. 4. It seems / appears (to sb.) that…
高中英语课件-it作形式主语及形式宾语句型
I would appreciate +it +if… 注意：表好恶的动词不能直接接宾语从句，
需要在从句前加上形式宾语it。
ห้องสมุดไป่ตู้
it的固定用法
When it comes to.... 当谈到…；
take it for granted that... 认为…理所当然
It is a fact(a pity, a shame, an honour，no wonder) +that从句 注：It is no good (use ) doing sth.(动名词短语做真正主语)
做某事是没益处(没有用的)的
注：区分常见的there be固定句型
There is no doubt that 毫无疑问 There is no need to do 没有必要 There is no point doing sth 做某事无意义
depend on it that...某人相信...
see to it that... 务必，保证
Let it be/go.
顺其自然；
That’s it. Make it. Get it.
对了，正是； 成功了； 懂了
一. it 用作形式主语 (1) It is+ adj. + that从句/to do sth
① It is clear, obvious,true,possible,certain.... that .....
“....是清楚（显然，真的，肯定）的” ② It is necessary, important, strange, natural.... that .....
It 的用法
It 的用法1：it 做形式主语，不定式to do 或that 引导的句子做真正的主语例句: It is important for us to protect environment. 保护环境对我们来说是很重要的。
（it 做形式主语，真正的主语是to protect environment）即to protect environment is important for us 是本句，但这样显得头重脚轻，所以用it 做形式主语.例句: It is common knowledge that science and technology is the first productive force.( it 做形式主语，that 引导的句子做真正的主语2：it 做形式宾语，不定式to do 或that 做真正的宾语例句：He thinks it very hard to master a foreign language.他认为掌握一门外语是很难的。
（he 做主语，thinks 做谓语，it 做形式宾语，very hard 做宾补，to master a foreign language 做真正的宾语，即He thinks to master a foreign language very hard.例句：He thinks it very essential that he should have a decent job.他认为他应该有一份体面的工作是很必要的即He thinks that he should have a decent job very essential.3: it 用于强调句，其结构是it is \was+强调部分+that例句：It was his carelessness that caused his fatal failure.正是他的粗心导致了他的致命失败。
（强调his carelessness,做caused的主语,即强调主语）例句：It was in the cinema that I came across my former English teacher.在电影院我巧遇我的前任英语老师。
“It”作形式主语和形式宾语的用法详解
it作形式主语和形式宾语一、it作形式主语：当不定式（短语）、动名词（短语）或从句在某个句子中作主语时，为保持句子结构前后平衡，避免头重脚轻，因此常用it作形式主语置于句首，而将真正的主语放在句尾。
此时it只起先行引导作用，本身无词义。
it作形式主语时，可以代替三种形式：不定式、动名词和主语从句。
1. it代替不定式短语常用于下列句型中：如：It is everyone’s duty to obey the law.遵守法律是每个人的义务。
It is difficult for a foreigner to learn Chinese.对于一个外国人来说，学习汉语是困难的。
It took them a year to build the bridge.建这座桥花了他们一年的时间。
It is bad manners to stare at people.瞪着眼睛看人是不礼貌的。
It is up to us to help those in need.帮助那些有困难的人是我们的责任。
eg. It’s important for us to learn English well.学好英语对我们来说是重要的。
It’s kind of you to help me.感谢你对我的帮助。
⒉ it代替动名词短语：It’s no good/use/useless/a waste of time doing sth.做某事没有用/浪费时间①It is no good/ use having a car if you can’t drive.如果你不会开车，有车也没用。
②It is a waste of time watching TV.看电视是浪费时间。
（it作形式主语,代替动名词短语watching TV）⒊ it代替主语从句：这个主语从句可以用连词that引导，也可以用连接代词或连接副词引导。
如：①It was clear that they had no desire for peace.很清楚他们没有和平的诚意。
英语中it的用法
it 在英语中的意思较多，用法较广，现总结如下。
一、it作句子的真正主语1．it 指前面已经提到过的人或事物，有时指心目中的或成为问题的人或事物，作真正主语。
例如：What’s this? －It is a sheep? 这是什么？？这是一只绵羊。
Who is it? －It’s me (I). 谁？？是我。
It’s the wind shaking the window. 是风刮得窗户响。
2．it指时间、季节。
一般用在无人称动词的主语。
例如：What time is it? －It’s nine. 几点了？？九点了。
It’s time for the meeting. Let’s go. 开会的时间到了，我们走吧。
What day is today? －It’s Saturday. 今天星期几？？今天星期六。
What’s the date today? －It is October 1st.今天是几号？？今天是十月一日。
What season is it? －It is summer. 现在是什么季节？？是夏季。
3．it 指气候。
一般作无人称动词的主语。
例如：Is it cold in this room? －No, it isn’t. 屋里冷吗？？不冷。
What’s the weather like today? －It is fine.今天天气怎么样？？是晴天。
It often rains in summer and it often snows in winter in this city.这个城市夏天经常下雨，冬天经常下雪。
4．it指距离、情况等。
一般用作无人称动词的主语。
例如：It is five kilometers from my home to the school.从我家到学校有五公里。
It is very near from this factory to that one.从这个工厂到那个工厂非常近。
It 的用法
It 的用法在英语中，It有许多不同的用法，它既可以用作代词（如人称代词，非人称代词），也可以用做引导词（作形式主语或形式宾语），还可以用来构成强调句型等。
一、It 用做人称代词1.It 可用作人称代词，指前面已经提到的事物，动物或人,指人主要用于指性别不明的婴儿或用于确认某人的身份。
He bought a dictionary and gave it to me.The bady is crying. It might be hungry.Someone is ringing. Who might it be?Professor Lee gave us a lecture yesterday. It was of great interest.【说明】在答语中，常用来指本人，如说It's me。
二、It 用作指示代词1.在"It is/was+表语"结构中，it指明某人或某物的身份，如：①—Who is there downstairs? —It's the postman.②—Who is there talking? —It's your father.2.指代this 或that以及复合不定代词something, anything, nothing等。
①—What's that on the desk? —I guess it might be a robot.②This is your plan, isn't it? ③Nothing is wrong, is it?三、It 用作非人称代词It 用作非人称代词，常指代天气，季节，距离，时间或事物的状态。
It was raining when I left the office.It's February 14th today. It's a long time since we met last time.It's an hour's walk from my home to the school.It's so noisy in the room.四、It 用作形式主语当不定式、动名词、从句等复杂成分用作句子主语时，为保持句子平衡，通常把真正的主语放在句末，而在句首使用形式主语it。
“It”作形式主语和宾语
“It”作形式主语和宾语it作形式主语和宾语A形式主语⑴It’s +adj. +for/of +sb. to do sth.It’s very kind of youIt’s important for you to learn English well.⑵It’s time for sb.to do sth.It’s time for you to sing⑶It seems that .....It seems that you are right.⑷It’s one’s turn /job/duty to do sth.It’s your turn/job/duty to clean the desk.⑸It’s +adj. that 从句It’snecessary/certain/natural that he wiil win.⑹It’s no use /good doing sth.做某事没有用处/好处。
It’s no use /good eating too much⑺It’s +一段时间since +一般过去时态从句或It has been +some time +since +一般过去时态从句It’s(been) five years since we saw last .⑻It’s a pity that ......It’s a pity that only six pieces of music in total were recorded for the future world to hear.⑼It is said that/It is consider that/It is believed that ......It is said that he became a famous pianist.B形式宾语动词(feel，think，make,believe,consider,suppose 等)+it +adj./n.+ to do sth.I think it necessary to learn English well.。
it用法大全(形式宾语形式主语)
3）.It +n+that ... 1. It is a pity ( a shame ... ) that ...
that后的从句一般用虚拟语气（should + 动词原形）， should可省去．表示出乎意料，常译为“竟然”。没有 这种意义时，则不用虚拟语气。
It doesn’t matter if they are old.
.2.作形式主语替代不定式
1). It takes sb. ... to do sth. ＂做．．．要花费某人．．＂ It took thousands of people many years to build the Great Wall.
2.非人称代词it
it有时并不指具体的东西，而泛指天气、时间、环境等， 称为非人称的it： 2.1.指天气： It is a lovely day, isn’t it? It is a bit windy.
2.2.指时间: It was nearly midnight when she came back.
2）.It is +v-ed +that 从句 ① It is said (reported， learned....) that ...
据说（据报道，据悉．．．）“。 It is said that he has come to Beijing.
= He is said to have come to Beijing.
难怪他不愿去。 在该句型中如果用肯定形式，表示“真奇怪， 真是令人惊讶”；
It is a wonder that he reused such a good offer.
it作形主语的五种
it作形主语的五种IT 作为形式主语的五种情况如下：1. 结构：It + be/have/do + 名词/代词+ 形容词/副词/动词-ing/动词过去分词等形式。
例子：-It is said that he is going to join our team.（据说他将要加入我们的团队。
）-It has been raining since morning.（自从早上就一直下雨。
）2. 结构：It + 动词过去分词+ 名词/代词+ 形容词/副词等形式。
例子：-It seemed like a good idea at the time.（当时看来这是一个好主意。
）-It occurred to me that we had met before.（我想起来我们之前见过面。
）3. 结构：It + 动词-ing + 名词/代词+ 介词+ 宾语等形式。
例子：-It's interesting to learn about different cultures.（了解不同的文化很有趣。
）-It's important to keep the environment clean.（保持环境整洁很重要。
）4. 结构：It + 动词-ing/动词过去分词+ 副词等形式。
例子：-It's been a long time since we last met.（自从我们上次见面已经过去很长时间了。
）-It doesn't matter if he doesn't know.（他不了解没关系。
）5. 结构：It + 动词-ing/动词过去分词+ 宾语等形式。
例子：-It happened that I knew the person involved.（碰巧我知道涉及的那个人。
）-It occurred to me that I hadleft my wallet at home.（我想起来我把钱包忘在家里了。
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②. It is important ( necessary， right， strange， natural...) that ... that 后的从句中要用虚拟语气（should + 动词原形）， should 可以省去，建议记住该句型中的形容词。 It is important that we (should) learn English well.
2) It was I that/who met your father in the street yesterday．
④强调句中也要注意主谓一致、人称一致和否定转移 的问题。
It is they who are our friends． It was not until ten o'clock that we got home last night．
2）.It is +v-ed +that 从句 ① It is said (reported， learned....) that ...
据说（据报道，据悉．．．）“。 It is said that he has come to Beijing.
= He is said to have come to Beijing.
A. it, it
B. what, what
C. it, what
D. what, it
㈡.引导词it 1. It is + 被强调部分 + that ...
使用该句型有以下几点请注意： ① 强调句的谓语is或was永远用单数.
It was yesterday that I met your father in the street．
It’s kind of you to help me. 你帮助我真是太好了。 (3) It is up to sb. to do sth.“应由某人负责”或 “……是某人的职责”。 It’s up to you to decide whether to take the job or not. 接不接受这份工作由你自己定。
It doesn’t matter if they are old.
.2.作形式主语替代不定式
1). It takes sb. ... to do sth. ＂做．．．要花费某人．．＂ It took thousands of people many years to build the Great Wall.
It looks as if he were ill. （没有生病）
It seemed as if he were dying.
if ) ...
该句型中whether(if) 引导的从句是真正主语， 该句型常译为＂不论（是否）．．．没关 系．．．。
It suddenly occurred to/struck me that I hadn’t seen Peter all day. 我突然想到，我一整天都没看见彼得。
(9) It is said/reported/announced/ (well) known…that… It is known to us all that he means well.我们都知道他
4) It is up to sb. to do sth.
It is up to him to clean our classroom today. 今天应由他做教室清洁。 It is up to parents to teach their children manners. 该由父母教孩子礼貌。
②. It is suggested ( ordered / demanded/ insisted/ commanded... ) that ...
主句中的过去分词是表示请求，建议，命令等词时， that 后的从句要用虚拟语气（should + 动词原形）， should 可以省；常译为“据建议；有命令．．．）
5) It is one’s turn to do sth.
It is your turn to clean our classroom today.
今天该轮到你做教室清洁。
.3.作形式主语替代ing形式
It is no good (use ) doing sth. 该句型中的真正主语是动名词短语，主句中的表 语可以是no good , no use ,useless
用过去时态表示虚拟．常译为“是（正是）．．．的时 侯．．．” / should+原型
It is time that children went to bed. It is high time that the children should go to school.
3. It is the first ( second ... ) time that ... “是第一（二）．．．次．．．”。 该句型中的 that 从句用完成时态。如果主句动词be是一般现 在时，后面从句用现在完成时态；如果主句动词be是一般过 去时，后面从句则用过去完成时态。该结构中 that 可以省去。 例如： It was the first time that I had been praised.
②不管被强调部分是哪种状语，只能用 that连接，不得使用where、when等连词.
It was in the street that I met your father yesterday．
③被强调部分为人时，可用who(主格或宾格)和 whom(宾格)代替that，用that也行。
1) It was your father that/whom /who I met in the street yesterday．
It is a pity that such a thing ( should ) happen in your class.
It is a pity that he is ill.
2. It is time ( about time ，high time ) that ... 该句型中that 后的从句应该用虚拟语气，值得注意的是常
It is suggested that the meeting ( should ) be put off.
3）.It +n+that ... 1. It is a pity ( a shame ... ) that ...
that后的从句一般用虚拟语气（should + 动词原形）， should可省去．表示出乎意料，常译为“竟然”。没有 这种意义时，则不用虚拟语气。
It is no good learning English without writing English.
It's useless trying to argue with Shylock.
4). It is/was not until....that... It was not until his mother came back that he turned off the TV.
(4) It is adj.＋ that--clause
It is important that we should pay close attention to grain.关注粮食对我们很重要。 (5) It is (no) good/use/useless ＋ doing sth. It is no use trying again ＝ It is of no use to try again. 再试也没用。 (6) It is worthwhile ＋ doing sth./to do sth.
It is worthwhile spending/to spend much time on it. 在这件事上花时间是值得的。
(7) It happens ＋ that--clause It happened that John was the only witness.碰巧约翰
是唯一的证人。 (8) It occurs to/strikes sb.＋that--clause 某人突然想 到……
难怪他不愿去。 在该句型中如果用肯定形式，表示“真奇怪， 真是令人惊讶”；
It is a wonder that he reused such a good offer.
真奇怪，他拒绝了这样好的帮助。
4). It+v+that从句 It happens (seems， looks， appears ) that...
It is the first time I have been here. = This is the first time I have been here.
4. It is no wonder that…
It is no wonder that he didn’t want to go. ＝No wonder he didn’t want to go.
it用法大全形式宾语形式主语
2.4.指距离： It is half an hour’s walk to the city centre.
㈠ 1.it作人称代词
Everyone knows that _______ is dangerous to play with fire, but _______ is difficult is to prevent children from playing with fire.