高中英语语法知识之It的用法总结讲解学习
it作为代词的用法总结
it作为代词的用法总结一、it 作为人称代词1. 表示特指的人或物：当我们想要提及已经被提到过的人或物时，可以使用 it 来代替。
例如：I saw a bird in the garden this morning. It was singing beautifully.2. 表示不具体指向的事物：当我们谈论天气、时间等与特定对象无关的概念时，可以使用 it。
例如：It is raining outside.What time is it?3. 用于强调句子中的主语或宾语：在强调句型中，it 可以用来指代原本句子中的名词，并将其放在句首。
例如：It was John who ate all the cake.It was the cat that knocked over the vase.二、it 作为形式主语或形式宾语1. 当真正的主语或宾语是一个从句时，我们通常使用 it 作为形式主语或形式宾语。
例如：It is important to exercise regularly.I find it difficult to understand his accent.2. 当强调整个动作而不是特定执行者时，也可使用 it 作为形式宾语。
例如：I find it interesting to learn new languages.She found it hard to say goodbye.三、it 作为虚主语1. 在一些较长的句子中，如果没有一个具体的主语和动词，我们可以使用 it 占据主语的位置，以保持句子的语法结构平衡。
例如：It is important to study before the exam.It seems that nobody is home.2. 在许多固定短语中，it 作为一个虚拟主语引入一个句子。
例如：It is said that he will be promoted soon.It doesn't matter if we arrive late.四、it 作为指代前文提到的内容1. 当我们在上下文中已经谈论过某个事物，并且想要通过代词回指时，可以使用 it。
高中英语语法知识之It的用法总结
高考英语语法知识之It 的用法总结1. It is + 被强调部分+ that ...该句型是强调句型。
将被强调的部分放在前面, 其它部分置于that之后。
被强调部分可以是主语, 宾语, 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。
I.wa.the.tha.(who.cleane.th.classroo.yesterday.I.wa.i.th.stree.tha..me.he.father.2. It was 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.no....unti....的强调形式. It was not until she took off her dark glasses that I realized she was a famous film star.= Not until she took off her dark glasses did I realize she was a famous film star...didn’.realiz.sh.wa..famou.fil.sta.unti.sh.too.of.he.dar.glasses.3. It is clear ( obvious, true, possible,certain....)that .....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 is very clear that he’s round and tall like a tree.= That he’s round and tall like a tree is very clear.4.I.i.importan..necessary.right.strange.natural....tha....由于主句中的形容词不同, tha.后的从句中要用虚拟语气（shoul..动词原形）, shoul.可以省去。
高中英语语法——It的用法
高中英语It的用法一、代词It1.用作人称代词，代替上文出现的同一个事物，既可以指代可数名词，也可以指代不可数名词, 其复数形式是them。
如：---Have you seen my pen? ---Yes, it’s in the desk.★ it可以指人，多指婴儿或指身份不明的人（通常是只闻其声，不见其人时）。
例如: ---Who is knocking at the door? ---It must be Tom.★ it与one和that的区别：one指代单数可数名词，泛指同类事物中的一个；其复数形式是ones，泛指一些。
如：I prefer a flat in east district to one in west district.that用来替代前面提到的特指事物，既可以指代单数可数名词，也可以指代不可数名词。
代替单数可数名词可以用the one替代。
其复数形式是those,指代复数名词，表特指。
如：The weather here is not so good as that there.The days in summer are longer than those in winter.2. it用以代替指示代词this和thatA：Whose umbrella is that?B：It’s Mary’s.3. it用作非人称代词，表示时间、日期、地点、天气、温度、距离、环境等。
It’s a beautiful day.It’s time for the meeting.课堂练习1. Tom's mother kept telling him that he should work harder, but ____didn't help.A. heB. whichC. sheD. it2. We’ve been looking at the houses but haven’t found ____ we like yet.A. oneB. onesC. itD. them3. The Parkers bought a new house but ____ will need a lot of work before they can move in.A. theyB. itC. oneD. which4. I was disappointed with the film. I had expected ________to be much better.A. thatB. thisC. oneD. it5. ---Do you like ___ here?---Oh, yes. The air, the weather, the way of life. Everything is so nice.A. thisB. theseC. thatD. it6. We need a new cupboard for the kitchen. So Peter made ____ from some wood we had.A. itB. oneC. himselfD. another答案：DABDDB二、引导词it1. it用作形式主语It is uncertain whether he can come to Jenny’s birthday party or not.It’s a pity that you missed the exciting football match.It remains a question whether he will come or not.It is reported that 16 people were killed in the earthquake.It happened that I was out when he called.It’s necessary for the young to master two foreign language.It is no use arguing about the matter with him.2. it用作形式宾语动词+形式宾语+宾语补足语+真正的宾语。
（完整版）It的用法总结
（完整版）It的用法总结It的用法总结在英语中,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)，也可以用作引导词（作形式主语或形式宾语），还可以用来构成强调句型。
.it用作代词(1) 用作人称代词在句子中作主语或宾语；指前面已经提到过的事物、动物或人，且it指特定的事物；如果指前文中提到的事物中的任何一个，用one。
one可以与any, each, every, not等连用，但one 不可代替不可数名词。
—where’s your car?—it’s in the garage. 你的汽车在哪儿呢？在车库里。
(指代物品your car)did you hit it? 你打中了吗？ (指代事件)the baby cried when it was hungry.这婴儿饿时就哭。
（指代婴儿，尤指性别不详或无所谓时）—who is that?—it’s me. 是谁？我。
(指一定情景中所确定的人或事物，此时相当于指示代词，代指this和that,有时也指人)—what’s this?—it’s a box. 这是什么？一只箱子。
(2) 作非人称代词表示天气、日期、时间、温度、距离、价值、路程、度量、自然现象与环境等。
也可模糊地指一般情形或上文的部分或整个意思。
译成汉语时，it通常不一定译出来。
it’s a long time since they left. 他们走后很久了。
it’s two miles to the beach.离海滨有两英里远。
that’s just it—i can’t work when you’re making so much noise.原因就在这里——你弄出这么大的声音，我工作不了。
另外，需要注意两点：（1）“it’s time…”后面可以接不定式和介词短语表示“是做……的时候了”。
如：it’s time for supper. it’s time to have supper.(2) “it’s time…”后面还可以接一个从句，但是从句中的谓语动词一定要用过去式即虚拟语气，如：it’s time we had lunch.是我们吃饭的时候了。
it用法总结高中
it用法总结高中【导语】作者在这里给大家带来it用法总结高中（共17篇），希望大家喜欢!篇1：高中it用法总结it作人称代词：1、指代事物。
作为人称代词，it 可以指除人以外的一切事物或动物。
如：Sam picked up some knowledge of the puter just by watching others working on it. 山姆只是凭借看别人操作电脑就学到了一些电脑知识。
(指the puter) (山东)2、指代人。
主要用于指婴儿或未知的人。
如：I was just going to cut my rose bushes but someone had done it. Was it you? 我正要剪切我的玫瑰丛但(发现)有人已经这样做了。
是你干的吗？(未知的`人) (湖南某)3、代替某些代词。
代词 it 还可用于代替指示代词this, that 以及复合不定代词 something, anything等。
如：—What’s this / that? 这/那是什么？—It’s an orange. 这/那是一个橘子。
it作非人称代词：1、it用于指时间、距离、价值、自然现象、环境等。
如：It rained heavily in the south, causing serious flooding in several provinces. 南方下了大雨，在几个省造成了严重洪灾。
(指自然现象) (天津某)2、it指代前面提到过的或谈话双方都明白的事情或情况。
篇2：it用法总结高中I didn't mean to break it— it was an accident.我不是故意打碎它的—这是个意外。
If it doesn't fit, you can always take it back.要是它不合适，你总还可以把它退回去嘛。
It didn't seem worthwhile writing it all out again.把这再都写出来似乎不必要。
it用法总结ppt课件
It was 3 days before he went to Beijing. It will be not long before he finishes his job.
8
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.
②. It is suggested ( ordered /demanded/insisted/commanded... ) that ...
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.
It is time that children went to bed.
② It is the first ( second ... ) time that ... “是第一（二）．．．次．．．”。
It is the first time I have been here. = This is the first time I have been here.
高中英语it的用法的归纳总结
高中英语it的用法的归纳总结以下是关于 it 的用法的一些归纳总结:1. 当 it 作为形式主语时，常用动词不定式或名词形式充当主语，其后面通常会加上 for 或 to 引导的短语。
例如：- It"s important to study hard.(努力学习很重要。
)- It"s a beautiful day.(今天天气很好。
)- It"s difficult to imagine a better place to live.(无法想象一个更适合居住的地方。
)2. 当 it 作为形式宾语时，通常用不定式或名词形式充当宾语，并在其后加上 for 或 to 引导的短语。
例如：- I appreciate your help.(感谢你的帮助。
)- It"s a great opportunity for me to learn new skills.(这是一个我学习新技能的好机会。
)- It"s necessary to clean the room.(打扫房间有必要。
)3. 当 it 作为实义主语时，表示某一具体事物或人物。
例如： - It"s a beautiful day, isn"t it?(今天天气很好，是吗？) - It"s yours, isn"t it?(这是你的吗？)4. 当 it 作为强调句的结构时，通常位于句首，其后是句子的主要成分。
例如：- I don"t know who it was that called me yesterday.(我不知道昨天是谁给我打电话。
)- It was yesterday that I visited my grandmother.(昨天我去看望了我奶奶。
)5. 当 it 作为单数名词时，通常指某一类人或物中的一个。
例如：- It"s a police car.(这是一辆警车。
高中英语it的用法课件-(详细有高考题-精品)
动词 +it + that + clause
enjoy, like, / love, dislike, appreciate hate, don't mind, be fond of, feel like, see to / depend on / insist on
例 : I hate it you can dance so well but I can't.
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： ⑴.指天气：
It is a lovely day, isn’t it? It is a bit windy.
⑵.指时间:
It was nearly midnight when she came back.
⑶.指环境:
no good 3. S + V + it +
no use
+ doing sth.
形式宾语归纳
该句型中的it 作形式宾语，记忆方便---“6123结构”。
6 主句中常用的动词： think,believe,make,find,consider,feel； 1 形式宾语it； 2 宾补的两种形式：形容词或名词； 3 真正宾语的三种形式：
an honour
…
… said It is / was p.p. known + that-clause believed
…
1. It is clear ( obvious， true， possible， certain....) that .....
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。
高考英语It的用法
高考英语It的用法It是高考英语中一个极其重要的词，其用法多样，在不同的语境中具有不同的意义。
下面我们将从it的用法、句型和固定搭配三个方面进行讲解。
一、it用作实词1、表示时间、天气、距离、温度等自然现象。
例如：It is Monday today.今天是星期一。
It is raining outside.外面正在下雨。
It is 5 kilometers away from here.距离这儿有5公里远。
2、表示观点、看法、态度等主观想法。
例如：I think it is a good idea.我认为这是一个好主意。
We think it is important to learn English well.我们认为学好英语很重要。
二、it用作形式主语当不定式、动名词或从句作主语时，为了保持句子结构平衡，避免头重脚轻，常用it作形式主语，代替不定式、动名词或从句，而把真正的主语放在句尾。
例如：It is important to learn English well.学好英语很重要。
It took me an hour to finish the homework.我花了一个小时完成作业。
三、it用作形式宾语当不定式、动名词或从句作宾语时，为了保持句子结构平衡，避免头重脚轻，常用it作形式宾语，代替不定式、动名词或从句，而把真正的宾语放在句尾。
例如：I think it is important to learn English well.我认为学好英语很重要。
He found it hard to learn English well.他发现学好英语很难。
四、it用于强调句型中强调句型是英语中一个重要的句型，用于突出强调某个成分，特别是主语、宾语和状语等。
在强调句型中，it没有实际意义，只是起到引导作用。
例如：It is I who am the best student in my class.我是班里最好的学生。
it的用法归纳高中
it的用法归纳高中高中阶段，“it”这个小小的单词，可是有着大大的用处！今天咱们就来好好归纳一下“it”在高中英语中的各种用法。
先来说说“it”作人称代词的时候。
这时候，“it”可以指代除人以外的一切事物或者动物。
比如说，“Look at the dog It is so cute”这里的“it”就是指代前面提到的“dog”。
“it”还能用来指代不明性别的婴儿或者身份不明的人。
想象一下，有人敲门，你不知道是谁，这时候你可能就会问：“Who is it?”再讲讲“it”作非人称代词的情况。
“It”可以表示天气、时间、距离、温度等等。
就像“It is sunny today”说的就是今天的天气晴朗。
“It's five o'clock”这就是在说时间是五点钟。
然后呢，“it”在高中英语中还有一个很重要的用法，那就是作形式主语或者形式宾语。
这个有点复杂，咱们慢慢说。
比如“It is important to learn English well”这里真正的主语是“to learn English well”，为了让句子看起来更平衡，就用“it”来作形式主语。
还有“It is ＋ adj ＋for/of sb to do sth”这个句型，同学们可得好好记住。
到底用“for”还是“of”，得看形容词是形容事情还是人。
如果是形容事情，就用“for”；要是形容人，那就用“of”。
比如说，“It is difficult for me to solve this problem” 这里“difficult”是形容“solve this problem”这件事，所以用“for”。
再看“It is kind of you to help me” 这里“kind”是形容“you”这个人，所以用“of”。
我想起之前教过的一个学生，他总是弄不清楚“it”作形式主语和宾语的用法。
有一次做作业，他错了好多相关的题目，那叫一个郁闷。
高考英语语法之it的用法
2. I hope there are enough glasse for each guest to have ________.(NMET 1995) A.it B.those C.them D.one 解析:答案为D.本题考查替代词it和 one的区别.it用于替代同类的,特定的, 同一的事物;one替代同类的,泛指的 人或物.根据题意"我希望有足够的杯 子使每个客人有一个."可知应用one 泛指enough glasses中的一个.
4)It is no use/ good + doing sth. It is no use trying again = It is of no use to try again. (5)It is + 被强调部分 + that/who + … Was it in the street that you met her? Who was it that called him "comrade"? It was not until yesterday that I met my old friend. It is in a small factory that my brother is going to work.(注意上述各句均为强调句型的"考点") 比较:It is a small factory where my brother is going to work.(定语从句)
(8)作形式宾语. I think it no use arguing with him. I found it very interesting to study English. He made it clear that he was not interested in that subject. (9)用于强调结构. It was Xiaoming whom ( that )I met in the street last night. It was in the street that I met Xiaoming last night. It ws last night that I met Xiaoming in the street.
高中英语It用法详解[共33页]
![高中英语It用法详解[共33页]](https://img.taocdn.com/s3/m/bde27d71168884868662d601.png)
It的用法解析1.it在强调句中用法：⑪It is + 被强调部分+ that …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时，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依据；①It was they that <who> cleaned the classroom yesterday.昨天是他们打扫的教室。
（强调主语）②It is her sister that I have fallen in love with.我爱上的是她的姐姐。
（强调宾语）③It was under the tree that he found his missing purse.他是在树底下找到自己丢失的钱包。
（强调地点状语）④It was last week that I visited the Shanghai Expo.我是上周参观的上海世博。
（强调时间状语）⑫It is not until + 被强调部分+ that …该句型是＂not… until…句型”的强调句，意为＂直到．．．才．．．＂，that后的从句要用肯定句，不可再用否定句；【注意：not until置于句首时，主句用倒装结构；】①It was not until she took off her dark glasses that I recognized she was a famous film star. （强调句）直到她摘下墨镜，我才认出她是一名著名的电影明星。
②Not until she took off her dark glasses did I recognize she was a famous film star. （倒装句）直到她摘下墨镜，我才认出她是一名著名的电影明星。
⑬强调句型的特殊疑问句结构：特殊疑问词+is/was + it + that …；①Who was it that you want to see? 你究竟想见谁？②Why is it that you want to change your mind? 你究竟为什么要改变主意？⑭强调句型的一般疑问句结构：Was/Is it +被强调部分+that…；①Was it they that cleaned the classroom yesterday? 昨天是他们打扫的教室吗？②Was it last week that you visited the Shanghai Expo?你是上周参观的上海世博吗？【注意事项】⑪强调句型结构基本要点：①强调句型中，通常强调主语、宾语、状语等；一般而言，该结构<It is/ was … that …>不可以强调谓语，若强调谓语，则用助动词do/does/did，其后的谓语用动词原形；(a) She did go there alone.她确实是一个人独自去那儿的。
高中英语语法知识之It的用法总结
高考英语语法知识之It 的用法总结1．It is + 被强调部分 + that ...该句型是强调句型。
将被强调的部分放在前面，其它部分置于that之后。
被强调部分可以是主语，宾语，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。
It was they that (who) cleaned the classroom yesterday. It was in the street that I met her father.2．It was 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.= Not until she took off her dark glasses did I realize she was a famous film star.= I didn’t realize she was a famous film star until she took off her dark glasses.3．It is clear ( obvious, true, possible,certain....) that .....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 is very clear that he’s round and tall like a tree.= That he’s round and tall like a tree is very clear.4. It is important ( necessary, right, strange, natural...) that ...由于主句中的形容词不同，that 后的从句中要用虚拟语气（should + 动词原形），should 可以省去。
高中英语代词it讲解（很完整的讲解）
高中英语代词it讲解（很完整的讲解）代词it一、指代前面提到过的名词，而且就是那个名词，即同类同物。
This is our new car. I bought it yesterday.I've bought a new bike and it cost me 100 dollars.二、指代前句所述的情况。
He smokes in bed and I don’t like it.Tom's mother kept telling him that he should work harder, but it didn't help.Yang Liwei was the first Chinese to be sent up into space. It made the Chinese proud.三、指动物或不考虑性别的婴儿。
Where is the cat? It’s under the bed.The baby cried when it was hungry. Is it a boy or a girl?四、在情景中确认某人或事物。
Who is it? It’s me. What’s this? It’s a map.There is a knock on the door. It must be the postman.五、指时间、距离、天气或环境等It is snowing. It was very quiet in the garden.What time is it? It’s seven o’clock.It’s time for supper. =It’s time to have supper.It’s about 50 kilometers from here to my home.六、It takes/took sb + 时间段+ to do sth. 某人做某事花了……时间。
高中英语语法It的用法总结
高中英语语法It的用法总结一、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 one'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/concern/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。
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高考英语语法知识之It 的用法总结1．It is + 被强调部分+ that ...该句型是强调句型。
将被强调的部分放在前面，其它部分置于that之后。
被强调部分可以是主语，宾语，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。
It was they that (who) cleaned the classroom yesterday. It was in the street that I met her father.2．It was 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.= Not until she took off her dark glasses did I realize she was a famous film star.= I didn’t realize she was a famous film star until she took off her dark glasses.3．It is clear ( obvious, true, possible,certain....) that .....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 is very clear that he’s round and tall like a tree.= That he’s round and tall like a tree is very clear.4. It is important ( necessary, right, strange, natural...) that ...由于主句中的形容词不同，that 后的从句中要用虚拟语气（should + 动词原形），should 可以省去。
It is important that we (should) learn English well. It is necessary that he (should) remember these words.5. It is said (reported, learned....) that ...该句型中的it 仍是形式主语，真正主语是that 引导的主语从句。
该结构常译为＂据说（据报道，据悉．．．）＂。
It is said that he has come to Beijing.6. It is suggested ( ordered ... ) 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．．It is suggested that the meeting ( should ) be put off.It was ordered that we ( should ) arrive there in two hours.7. It is a pity ( a shame ... ) that ...该句型中，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 a pity that such a thing ( should ) happen in your class. It is a pity that he is ill.8. 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①常用过去时态表示虚拟．②有时也用should + 动词原形，should 不能省。
常译为＂是（正是）．．．的时侯．．．＂。
It is time that children should go to bed. = It is time that children went to bed.9. It is the first ( second ... ) time that ...该句型中的that 从句不用虚拟语气，而用完成时态。
至于用什么完成时态，由主句的谓语动词的时态决定。
如果是一般现在时，后面从句用现在完成时态；如果是一般过去时，后面从句则用过去完成时态。
该结构中that 可以省去；it有时用this / that 替换．常译为＂这是某人第几次做某事了＂。
It is the first time I have been here. = This is the first time I have been here.10 It is the +形容词最高级+ 名词+ that + …..该句型中的that 从句不用虚拟语气，而用完成时态。
至于用什么完成时态，由主句的谓语动词的时态决定。
如果是一般现在时，后面从句用现在完成时态；如果是一般过去时，后面从句则用过去完成时态。
该结构中that 可以省去；it有时用this / that 替换．常译为＂这是某人做过的最…的事情＂。
This is the best film that I have ever seen . That was the worst song that he had heard .11. It is .... since ...该句型主要用作处理瞬间动词的完成时，又要和表示一段时间的时间状语连用的问题。
主句中是时间作表语，其时态是现在时或完成时，since 引导的从句通常是一般过去时态，而且是瞬间动词。
如果主句是一般过去时，从句则用过去完成时。
It is ( has been ) 5 years since his father died.12. It is ... when ...该句型中的when 引导的是一个时间状语从句，主句中的it 指时间，表语由具体的时间充当。
常译为＂当．．．的时候，是．．．＂。
It w as 5 o’clock when he came here.比较：There was a time when + 定语从句（曾经一度….；有一个时期…）There was a time when Iraq was one of the strongest countries in the world .There was a time when I was disappointed and wanted to leave here .13. It be ... before ...该句型主句中的it 指时间, 主句中的时态常是将来一般时或过去时两种时态．主句中的表语多是long, not long , 3 days , 2 weeks 等表示时间段的词或短语。
常译为＂．．．之后．．．＂。
It was 3 days before he went to Beijing. It will be not long before he finishes his job.14. It happens (seems, looks, appears ) that...该句型中it是形式主语，that 引导的是主语从句，主句中的happen , seem等词是不及物动词．It happened ( so happened ) that he met his teacher in the street. 碰巧．．It seems that he will be back in a few days. 看来．．．15. It looks ( seems ) as if ...该句型中it无意义。
as if 引导一个状语从句。
常译为，＂看起来好象．．．＂如果与事实不相符合，则用虚拟语气．It looks as if he is ill.It looks as if he were ill. It seemed as if he were dying.16. It takes/costs sb. ... to do sth.该句型中的不定式是真正的主语，it是形式主语，句型中的直接宾语是时间。
常译为＂做．．．要花费某人．．．＂。
It took thousands of people many years to build the Great Wall.注意：当主语和表语都是不定式时，不能用it 作形式主语代替动词不定式。
To see is to believe . To respect others is to be respected .17. It is kind ( of sb. ) to do sth.该句型中的不定式短语是真正主语，如果不定式的逻辑主语是由of引起，主句中的形容词必须是能表示逻辑主语特征的形容词。
常见的有：bad , brave , careless, clever , cruel , foolish , good （好心的）, honest , horrible , kind , lazy , modest , naughty , nice（有教养的）, polite, rude , silly , stupid , wise , wrong（错误的）等。
这个句型可以改写为：sb. is kind to do sth.It is kind of you to say so. = You are kind to say so.18. It is necessary ( for sb. ) to do sth.如果不定式的逻辑主语是由for引起，主句中的形容词通常是表示重要性，紧迫性，频繁程度，难易，安全等情况的形容词。
常见的形容词有：①important, necessary, natural ②easy , safe , common , normal , hard , difficult , dangerous , unusual, rare , impossible , pleasant等。
在①中的形容词作表语可以用从句改写，It is important for her to come to the party. = It is important that she (should ) come to the party19. It is no good / use / fun doing sth.It is a great pleasure / a waste of time / a bore doing sth .It is useless / nice / good doing sth .该句型中的真正主语是动名词或动名词短语，主句中的表语可以是名词或形容词。