浅谈it作形式主语的用法
“It”作形式主语和形式宾语的用法详解
新希望英语语法精讲------“It”作形式主语和形式宾语“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用法，是英语学习的主要语法项目之一。
无论是单项选择，还是完行填空，it 用法始终是反复考查的重、热点之一。
现将it在特殊句型中作形式主语和形式宾语用法，进行如下归纳分析，以供学习参考。
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：①It + 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。
)②It + be +名词词组+ doing / that ….e.g. It is no good telling lies. (撒谎没好处。
)It is a pity that you didn’t go to see the film yesterday. (你昨天没看成那部电影真遗憾。
it作形主的用法
it作形主的用法“It作形主的用法”是指使用it做形式主语，即在句子中无实际含义的主语，通常是一些动词、表语或状语从句。
it这个词有多种用法，因此它可以用来代替不同的句子成分。
在英语中，it作形主语最常用于三种情况：1、it作形式主语：在英语中，it常常被用作形式主语，以强调句子的其余部分。
例如：It is said that he is a very good student.It is believed that the earth is round.2、it作形式宾语：it也可以用作形式宾语，用来代替一个真正的宾语，强调句子的其余部分。
例如：She made it clear that she wouldn't go.He proved it wrong that he was not guilty.3、it作形式状语从句：it也可以用作形式状语从句，用来代替一个真正的状语从句，强调句子的其余部分。
例如：He said it as if he had known everything.He did it as though he had done it many times before.此外，it还有一种特殊的用法，即在句中作为虚拟语气的主语。
这种情况下，it用来引出一个虚拟条件句，带有一种意思是“如果……”。
例如：If it rains, we will stay at home.It would be nice if you could come to my party.以上就是“it作形主的用法”的详细说明。
从上文可以看出，it作形式主语、形式宾语和形式状语从句，并在句中作为虚拟语气的主语，是一种常见的用法。
只要我们能够正确地理解它的用法，就能够在日常的学习和交流中正确使用它。
it做形式主语时的用法
it做形式主语时的用法It作为形式主语时，常常用于代替后面真实主语的从句、动名词或不定式，以避免句子结构显得过于复杂或者不平衡。
以下是It 作为形式主语的几种常见用法：1、It + be + 形容词 + that从句：这种句型中的形容词通常是表示性格、品质的形容词，如nice、kind、stupid等。
例如：It is kind of you to help me. 你真好，帮了我。
2、It + be + 名词 + that从句：这种句型中的名词通常是表示时间、距离、度量衡等概念的名词。
例如：It is five years since we last met. 我们上次见面已经五年了。
3、It + be + 介词短语/副词 + that从句：这种句型中的介词短语或副词通常用来描述地点、方式等。
例如：It is in this room that we had the party. 我们就是在这个房间里开派对的。
4、It + be + 动词的过去分词 + that从句：这种句型中的动词过去分词通常是表示完成的动词，如known、heard、seen等。
例如：It is said that he has gone abroad. 据说他已经出国了。
5、It + be + 不定式短语/动名词 + that从句：这种句型中的不定式短语或动名词通常用来描述将来的动作或一般性的情况。
例如：It is to study hard that he will succeed. 他只有努力学习才会成功。
需要注意的是，在It作为形式主语的句子中，真正的主语通常是一个从句或非谓语动词短语，这些从句或短语被放在句子的后面，以保持句子的平衡和流畅。
It作形式主语常见用法
It作形式主语常见句型1.It + be +形容词+ that-从句可用于此句型的形容词有: wonderful, true，good，right，wrong，（un）important，useless，surprising，disturbing,frightening,alarming,clear，unusual，lucky，certain, necessary等。
如：①It is quite certain that he will be at the meeting.他将出席会议是无疑的。
②It is surprising that he came late to school this morning.他今天早上迟到真令人惊讶。
③It is important that we (should) study hard.我们努力学习是很重要的。
注意: 该句型中的形容词是（un）important, necessary等时，从句应为(should )+动词原形。
It is important that we (should) learn English well.It is necessary that he (should) remember these words.2.It + be +名词+ that-从句适用该句型的名词（词组）有: a pity，an honor，a good thing，a fact，a surprise，a question,a shame,a custom, a truth,our hope, no wonder, good/bad manners等。
如：①It is a pity (that) you missed the sports meeting last week. 你错过了上周的运动会太可惜了。
②It is a fact that English is being accepted as an international language. 事实上英语已经被作为一种国际语言而接受了。
“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”作形式主语和形式宾语用法详解
新希望英语语法精讲------“It”作形式主语和形式宾语“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用法，是英语学习的主要语法项目之一。
无论是单项选择，还是完行填空，it 用法始终是反复考查的重、热点之一。
现将it在特殊句型中作形式主语和形式宾语用法，进行如下归纳分析，以供学习参考。
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：①It + 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。
)②It + be +名词词组+ doing / that ….e.g. It is no good telling lies. (撒谎没好处。
)It is a pity that you didn’t go to see the film yesterday. (你昨天没看成那部电影真遗憾。
It作形式主语和形式宾语的用法详解
新希望英语语法精讲------“It”作形式主语和形式宾语“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用法,是英语学习的主要语法项目之一;无论是单项选择,还是完行填空,it用法始终是反复考查的重、热点之一;现将it在特殊句型中作形式主语和形式宾语用法,进行如下归纳分析,以供学习参考;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;. 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：①It + be + 形容词+ to do sth. / doing / that ….. 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;②It + be +名词词组+ doing / that ….. It is no good telling lies. 撒谎没好处;It is a pity that you didn’t go to see the film yesterday. 你昨天没看成那部电影真遗憾;It is a truth that there would be no new China without the Communist Party.没有共产党就没有新中国,这是毋庸质疑的;③It + be + 过去分词+ that ….该句型常见动词有：say, hope, think, suppose, expect, report, know, believe, decide, etc.. It is said that they have invented a new type of computer. 据说他们发明了一种新型电脑;It is believed that China will become one of the strongest countries in the world.大家都相信中国将会步入世界强国之列;It was reported that more than 170 thousand people died in the 2004 tsunami.据报道,至少有十七万人在2004年那场海啸中丧生;④It + seems / appears / happens等不及物动词+ that ….. It seems that he enjoys pop songs very much.似乎他非常喜欢流行歌曲;It appears that Tom might change his mind. 看来汤姆可能会改变主意;⑤若句子是疑问形式,就只能用it作形式主语;. Does it matter much that they won’t come tomorrow他们明天不来很重要吗Is it true that he will go abroad next week 他下周出国是真的吗⑥It + takes + sb. + some time + to do sth. 这是一个表示“某人花多少时间干某事”的句型,其中it是形式主语,代替后面的不定式to do sth.,句型中的sb.也可以省略;. It took me some time to read the reading materials.我花了一些时间才读完那段阅读材料;It took him fourteen hours to go to New Zealand from Shanghai by plane.从上海乘飞机去新西兰花了他14小时;How long does it take you to go to Beijing from Qingdao by train从青岛坐火车到北京一般要花多久时间I am not sure, but I think it takes at least nine hours to get there.我不能肯定,但估计至少要九个钟头才能到那儿;二、It 用作形式宾语当不定式短语、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;下列四种情况须用it 作形式宾语：①当不定式短语、动名词短语或从句在复合宾语结构中作某些动词的宾语时如think, make, find, consider, feel, suppose等；. They found it pleasant that they worked with us Chinese.他们发现与我们中国人一起工作很愉快;I don’t feel it difficult to understand the Special English. 我觉得理解英语特别节目并不难;He makes it a rule never to borrow money. 他立志决不向别人借钱;I think it no need talking about it with them. 我认为没必要跟他们谈;②某些表示“喜、怒、哀、乐”的动词,如like, enjoy, love, hate等,往往不能直接接宾语从句；. I don’t like it that he’s so lazy. 我不喜欢他那么懒惰;I hate it when my mother asks me to eat eggs. 我讨厌母亲要我吃鸡蛋;③that引导的宾语从句不能直接作介词的宾语；. You may depend on it that we shall always help you. 尽管放心,我们会随时帮你的;Would you see to it that she gets home early 你负责保证她早到家,好吗He insisted on it that he was innocent. 他坚持说自己是无辜的;④由及物动词与介词组成的固定搭配中,宾语从句若作该动词的宾语时,须借用it;. I leave it to your own judgement whether you should do it. 我让你自己判断这事是否该做;We owe it to you that there wasn’t a serious accident. 多亏了你才没有发生严重事故;练习一1. Is _______ necessary to complete the design before National DayA. thisB. thatC. itD. he2. I don’t think _______ possible to master a foreign la nguage without much memory work..A. thisB. thatC. itsD. it3. Does _______ matter if he can’t finish the job on time A. this B. that C. he D. it4. Tom’s mother kept telling him that he should work harder, but ____ didn’t help. A. he B. whic h C. she D. it5. _____ is a fact that English is being accepted as an international language. A. There B. This C. That D. It6. I hate _______ when people talk with their mouths full. A. it B. that C. these D. them7. Don’t _______ that all those who get good grades in the entrance examination will prove to be the most successful. A. take as granted B. take this for granted C. take that for granted D. take it for granted8. I like _______ in the autumn when the weather is clear and bright. A. this B. that C. it D. one练习二1. _______ happened _______ he is unfit for the . This; that B. That; that C. It; that D. He; that2. We took _______ for granted that they would accept our . that B. this C. it D. them3. ______ that the scientist will give us a talk next month A. Is true B. Is it true C. It’s true D. It’s truly4. ____ doesn’t matter much _____ dress you are going to . This; that B. That; who C. It; which D. It; who5. _______ is going to America for further study.A. He is said thatB. People said that heC. It was said heD. It is said that he6. They are good friends. _______ is no wonder that they know each other so . This B. That C. There D. It7. Is _______ possible to fly to the moon in a spaceship A. this B. there C. that D. it8. She liked _______ when he kissed her. A. him B. that C. one D. it9. _______ will do you good to do some exercise every morning. A. It B. There C. Those D. One10. We think _______ our duty to pay taxes to our . that B. this C. its D. itKey: 练习一1-8 CDDDDADC 练习二1-5 CCBCD 6-10 DDDADit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 law②It 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 Chinese③It 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 dumps④It 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 bridge⑤It is bad manners to stare at people.瞪着眼睛看人是不礼貌的;it作形式主语, 代替不定式短语to stare at people⑥It is up to us to help those in need.帮助那些有困难的人是我们的责任;it作形式主语, 代替不定式短语to help those in need⑦It is not up to you to tell me how to do my job.我怎样干我的工作不用你来多嘴;it作形式主语, 代替不定式短语to tell me how to do my job◆ It be + 形容词+ for sb. to do sth.与It be + 形容词+of sb. to do sth.：如果句型中的形容词描述的是sb.的品质、品格,在逻辑上可以作sb.的表语,则sb.前应用介词of,否则就用for;如：①It’s necessary for us to use a short-wave radio to pick up the programmes.我们用一台短波收音机收听这些节目是必要的;②It’s important for us to learn English well.学好英语对我们来说是重要的;③It’s kind of you to help me.感谢你对我的帮助;= You are kind to help me.④It was foolish of him to give up the job.他放弃那工作是愚蠢的= He was foolish to give up the job.⒉ it代替动名词短语：动名词作主语用后置形式的情况远不及不定式那么普遍,常限于no good, no use, useless, waste等词的后面;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;it作形式主语,代替动名词短语having a car②It 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 TV③It is no use asking him.问他没有用;it作形式主语,代替动名词短语asking him④It is no use talking to him about it.和他谈这事没有用; it作形式主语,代替动名词短语talking to him about it⒊ 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;it作形式主语,代替主语从句that they had no desire for peace②It is doubtful whether she will be able to come.她能否来还很难说;it作形式主语,代替主语从句whether she will be able to come③It was clear enough what she meant.她的意思是够清楚的; it作形式主语,代替主语从句what she meant④It hasn’t been made clear when the new road is to be opened to traffic.还没明确宣布新路什么时候通车; it作形式主语,代替主语从句when the new road is to be opened to traffic⑤It is a mystery to me how it all happened.这都是怎么发生的对于我来说还是一个谜;it作形式主语,代替主语从句how it all happened用it作形式主语,把真正的主语从句移至后面的常见句型有：◆ It is a pity/ a shame/ a fact/ an honour/ good news/ no wonder/ a wonder… that…如：①It was a pity that the engineer couldn’t come.可惜工程师没能够来;②It is a wonder that he continues to gamble when he always loses令人惊讶的是他一直输还一直赌;③It isno wonder that you were late难怪你来晚了;④It is a shame that the rain spoiled our picnic.真可惜,这场雨把我们的野餐给搅了;⑤It is a fact that English is being accepted as international language.英语被认为是国际语言,这是一个事实;◆It is + 形容词如：strange/ natural/ surprising/ obvious/ true/ fortunate/ wonderful/ funny/ possible/ impossible/ likely/ unlikely/ clear/ unusual/ certain/ important…that …如：①It is certain that he will win.他一定会取胜;②It is important that we should learn from each other and help each other.我们应当互相学习,互相帮助,这是很重要的;③It was obvious that the child had been badly treated.很显然那个孩子受过虐待;④It is likely that he will ring me tonight.他今晚可能给我打电话;⑤It is strange that he should have left without telling us. 真奇怪,他也没说一声就走了;⑥It is unlikely that their group will get ahead of us. 他们小组不会赶到我们前头去;◆ It seems/ happened/ turned out/ suddenly struck me/ occurred to me…that …如：①It happened that I wasn’t there that day.恰好那天我不在那里;②It seems that his idea is more practical.看起来他的意见更实际一些;③It suddenly occurred to me that I knew how to solve that problem.我忽然想起我知道怎样解决那个问题;◆It + be + 过去分词如：said/ reported/ announced/ decided/ expected/ hoped/ known/ believed…that…如：①It is hoped that the number of deer will greatly increase very soon.相当于：People hope that the number of deer will greatly increase very soon人们希望鹿的数目将会很快增加;②It is said that nothing has been done about it. 据说至今对此没采取任何措施;③It is reported that more than twenty people were killed in that bus accident.据报道在那次的公共汽车事故中有二十多人丧生;④It is known that he is one of the best teachers in our school.大家都知道他是我们学校最好的教师之一;⑤It is believed that the flood there is the biggest in 100 years.据认为那儿的洪水是百年来最大的洪水;注意要在It is suggested/required/desired/ordered/pr oposed…that…的主语从句中用虚拟语气：should + 动词原形如：①It is requested that he give a performance at the party.有人请求他在聚会上表演一个节目;②It is suggested that we should get everything ready by tonight.建议一切在今晚准备好;③It is ordered that the radio be sent there at once.据命令,这台收音机要立刻送到那里去;◆ It doesn’t matter +连接代词或副词…It doesn’t make too much difference+连接代词或副词…如：①It doesn’t matter whether he comes or not.他来还是不来都没关系;②It won’t make much difference whether you go today or tomorrow.你今天去也好,明天去也好,关系不大;㈡it作形式宾语：it作形式宾语时,可以代替三种形式：不定式、动名词和宾语从句;it作形式宾语时,需具备两个条件：①真正的宾语是不定式、动名词或从句②有宾语补足语具备了这两个条件,形式宾语it一定要用;1. it代替不定式短语think/ find/ feel/ consider/ make/ regard…+ it +形容词/名词+ 不定式短语如：①I find it pleasant to work with him.it 作形式宾语,代替不定式短语to work with him我觉得和他一起工作很愉快;②They felt it difficult to finish the work in such a short time.it 作形式宾语,代替不定式短语to finish the work in such a short time他们认为在这么短的时间内完成这项工作是困难的;③She thinks it her duty to help us. it 作形式宾语,代替不定式短语to help us她觉得帮助我们是她的责任;④I think it my honor to be invited to speak here.it 作形式宾语,代替不定式短语to be invited to speak here我觉得应邀在这儿演讲是我的荣耀;⑤Tom didn’t find it difficult to write letters in Chinese.it 作形式宾语,代替不定式短语to write letters in Chinese汤姆发现用汉语写信不难;⑥All these noises made it impossible for me to go on with the work.it 作形式宾语,代替不定式短语to go on with the work这些噪音使我无法继续工作;⒉ it代替动名词短语这只限于少数句型,在多数情况下用不定式时更多一些如：①The professor considers it no good reading without understanding.这位教授认为阅读而不理解没有益处;②Do you consider it any good trying again你觉得再试会有好处吗③He found it useless no use arguing with him.他发现和他辩论没有用;④He thought it absolutely senseless attempting the impossible.想做不可能的事情,他认为是完全没道理的;⑤I don’t think it worthwhile going to such a place.到这样一个地方去我看是不值得的;⒊it代替宾语从句：如：①We all thought it a pity that the conference should have beencancelled.会议取消了我们都感到很遗憾;②I took it for granted that they were not coming.我想他们准是不会来的了;③I’ll see to it that everything is ready in time.我负责使一切都按时准备好;㈢含it 的常用句型英语中有一些固定句型中含有it,应注意这些句型的使用;1. It be + 被强调部分+ that/ who + 其他成分强调句型可以强调一个句子的主语、宾语、表语及状语等成分;如果被强调的成分是表示人的词,可以用that或whowhom连接其他成分；被强调的成分是表示人以外的词,例如表示事物、时间或地点的词,用that连接其他成分;例如我们可以用强调句型强调下列句子的主语如⑴、宾语如⑵、地点状语如⑶及时间状语如⑷I met Peter in Japan last year.⑴ It was I who/that met Peter in Japan last year.⑵ It was Peter whom/that I met in Japan last year.⑶ It was in Japan that I met Peter last year.⑷ It was last year that I met Peter in Japan.not …until 也可用于强调句型例1Mr Brown didn’t come back until eleven o’clock.可变为：It was not until eleven o’clock that Mr Brown came back.例2 The rain didn’t stop until midnight.可变为：It was not until midnight that the rain stopped.强调句也可变为特殊疑问句例1It was in 1949 that the PRC was founded.可变为：When was it that the PRC was founded 例2 Your dad worked in this factory two years ago.可变为：Where was it that your dad worked two years ago2It’s + 地点状语+ that…强调句It’s +地点名词+ where… 定语从句如：①It is the town where I was born.the town 为地点名词,定语从句这是我出生的镇子;②It was in the town that I was born.in the town为地点状语,强调句型我出生在这个镇子;’s + 时间名词+ when…时间状语从句It’s + 时间状语+that…强调句如：①It was at 8 o’clock that he returned.at 8 o’clock是时间状语,强调句他是在八点钟回来的;②It was 8 o’clock when he returned.8 o’clock 是时间名词,时间状语从句他回来的时候是八点钟;4. if it is convenient to you 如果你方便的话如：If it is convenient to you, you can start tomorrow.如果方便的话,你明天可以动身;5. believe it or not 信不信由你如：①Believe it or not, I’ll go abroad next month.不管你信还是不信,我下个月要出国;②Believer it or not, we were left waiting in the rain for two hours.信不信由你我们冒雨等了两个小时;6. It’s time that…did / should do …定语从句如：①It is time that I went and picked up my daughter from school.我该去学校接我女儿放学了;②It’s high time that we stopped/should stop this practice.我们的确该停止这种做法了;7. It is /has been…since…did…时间状语从句如：It is just a week since we arrived here.我们来这里已一星期了;8.It won’t be …before…用不了多长时间就会…It will be…before…得过多长时间才…It wasn’t …before…没过多长时间就…It was…before…过了多长时间才…①It will be a long time before we finish the task.我们还需要很长时间才能完成这项任务;②It wasn’t long before he learned to use the computer.不久他就学会使用计算机了;③It was some time before he told me about this affair.过了一段时间之后他告诉了我这件事;④It won’t be long before we meet again.不久之后我们还会再见面的;㈣易混用其他句型英语中有一些句型不含it, 但却易被误用了it,常见的有以下句型：⒈ There is something/nothing wrong/ the matter with sb./ sth.如：There is nothing wrong /the matter with him. He’s just pretending.他没什么事,他只是在装呢;2. There is no doubt about…对…毫不怀疑There is no doubt that…对…毫不怀疑如：①There is no doubt about his suitability for the job.毫无疑问,他适合这个工作;②There is no doubt about the fact.关于这个事实毫无怀疑;③There is no doubt that he is hard to deal with.毫无置疑他很难对付;⒊ There is no need for sb. to do sth.没必要…如：①There was no need for him to remain in Paris.他没有必要继续留在巴黎;②There is no need for you to start yet.你现在还不必动身;is no/a possibility that… …没可能/有可能= It is impossible/possible that …如：①There is a possibility that the train may be late.可能火车要晚点;②There is no possibility that we’ll see him this weekend.我们本周末不可能见到他;is a chance t hat …可能…如：There is a chance that the sick child will get well.这个生病的孩子可能会好起来的;be no/ some differences between…and……和…之间没/有区别如：There are some differences between the two languages.这两种语言之间有些区别;7. After what seemed + 时间如：After what seemed a very long time, the wounded soldier came back to life.在经过似乎很长的一段时间之后,那个受伤的士兵苏醒了过来;8. There be difficulty/ trouble in doing sth.干…有困难如：here was no difficulty in finding him.找到他没费什么事;习题演练：is reported that he got seven gold . That B. Word C. It D. Newslong ______ to finish the workA. you will takeB. will you takeC. you will take itD. will it take youno need for us to discuss the problem again. It has already been settled.A. It hasB. There hasC. It isD. There iswas disappointed with the play. I had expected _____ to be much better.A. thatB. thisC. oneD. itdon’t think _______ possible to master a foreign language without much memory work.A. itB. thatC. itsD. this_______ matter if he can’t finish the job on time A. this B. it C. he D. thatyou need my ruler ----No, thanks. I’ve got _______ myself.A. itB. eachC. oneD. the oneperson do you mean----______ who wears a new gold watch.A. The oneB. OneC. EachD. It_____ three years since I left . has been B. was C. had been D. will bewon’t be long _____ the island ________ to our motherland.A. when, returnsB. before, will returnC. since, returnsD. before, returnsmany years is it ______ your family moved hereA. afterB. sinceC. beforeD. untilis a pity that you forgot both her address and her telephone number.A. ItB. ThereC. ThisD. Thatsaw no more than one copy left in the bookshop. Will you go and buy ______A. itB. someC. anyD. oneyou see to ______ that the luggage is brought backA. meB. yourselfC. itD. them_______ that she has lost interest in studying English.A. seemedB. appearsC. looksD. remainshappened that I met one of my friends . I B. That C. It D. Howthink _______ right that you didn’t tell him the bad . it B. its C. you D. that18. _______ to say which one I should choose.A. That’s hardB. It is hardC. There no useD. It no goodsurprised me most was that she had become a famous singer.A. ThatB. ItC. WhatD. Thiswill take you a lot of time to find him in the crowd.A. ItB. IC. WeD. Theyfelt ______ to work for human rights and progress.A. it his dutyB. his dutyC. that is a dutyD. that is his dutyin the west makes ______ a rule to buy Christmas presents for their relatives and friends.A. thatB. itC. thisD. The thingfurther discussion whether we’ll build a library or not.A. WeB. HeC. ItD. The thingis no good _______ without doing anything.A. This, talkingB. It, to talkC. It, talkingD. That, to talkis no difference between . There B. Where C. It D. Whatit _______ that they saw A. she B. that she C. her D. herselfbeing Sunday, the library was . That B. It is C. It D. Thiswas evening _______ we arrived . that B. when C. this D. sincewas in the village ______ now is a small town ________ the earthquake occurred.A. where, whichB. which, whereC. which, thatD. that, wherechildren are as bright as he is, and also, he works very hard.----It’s no ______ that he always gets the first place in any examination.A. questionB. doubtC. problemD. wonder答案与提示：it在此句中是形式主语,真正的主语是that从句;这个句型的结构是：it be +过去分词+that 从句;it takes sb. some time to do sth. 意为“花费时间做某事”;It是形式主语,代替不定式短语;此句是将来时态;本题用的是there be句型;There is no need to…是这个句型的一种表达方式,意思是“没有必要…”;I had expected的宾语是前面所提到的play;英语中,通常用it 和one来替代前面单数名词,可以选C或D, one所代替的是同类事物中“一个”,而it所代替的是前面提到过的同一事物,所以答案为D;to master a foreign language without much memory work是动词不定式短语作think的宾语;当句子的宾语是动词不定式或that从句时,我们通常用it作形式宾语,但是如果宾语不与形容词在一起,一般不能用it作形式宾语;本题是一般疑问句;matter有关系,要紧经常用于否定句和疑问句,常用句型是：Does it matter…It doesn’t matter…;不定代词one常用来代替与前面已提到的一个事物人或东西,以避免重复;one 表示同类事物中的“任一个”,即：表示泛指,而the one则表示确指;人称代词it被用来代替前面提到的那个东西;不定代词each常表示“每一个”的意思;根据题意你要用我的尺子吗不,谢谢;我自己有一支;和结构,应选C;不定代词one 和the one都可以被用来代替前面提到过的一个同类事物人或东西,以避免重复;one表示泛指,而the one表示确指;题意为：“你指的是哪个人”“那位戴一只新金表的;”It is /has been…since…did…时间状语从句意思为：自从…以来已有…时间了;It won’t be …before…“用不了多长时间就会…”,其中before引导的是时间状语从句,所以应用现在时态;It is /has been…since…did…时间状语从句意思为：自从…以来已有…时间了;题意为：你们家搬到这里已多长时间了It is a pity that…其中it是形式主语,that从句是真正的主语;one表示同类事物中的“任一个”,即：表示泛指;人称代词it被用来代替前面提到的那个东西;no more than 表示“仅仅,只有”;it 作形式宾语,真正的宾语是后面的that 从句;it seems/appears that…为固定句型,“似乎…”;选项A的时态不对;it happened that…为固定句型,意思是“碰巧…”;题意为：昨天我碰巧碰到了我一位朋友;it 作形式宾语,真正的宾语是“that you didn’t tell him the bad news”it 作形式主语,后面的不定式短语作真正的主语;what surprised me most 在本题中是主语从句;如果选B, 则应把原题中的was去掉,变为：It surprised me most that she had become a famous singer. it 做形式主语本题用的是句型：It takes sb. some time to do sth. 干…花了某人…时间;其中it作形式主语;feel/ find/ think / consider/ make/ regard…+ it +名词/ 形容词+不定式短语, 其中it做形式宾语,真正的宾语是“to work for human rights and progress”make / find/ think / consider/ feel / regard…+ it +名词/ 形容词+不定式短语, 其中it做形式宾语,真正的宾语是“to buy Christmas presents for their relatives and friends”it作形式主语,真正的主语是后面的从句“whether we’ll build a library or not”本题用的是句型：It is no good doing sth. 意思是“干…没用/好处” 其中it 作形式主语,用来代替后面的动名词短语;本题用的是固定句型：There is no difference between…意思是“和…之间没/有区别”,注意别误选it;本题为一个由强调句变成的一般疑问句,被强调的人称代词为宾格;原句应为：They saw her. 选项B的句子结构语法不对;It being Sunday是独立主格结构,在此相当于原因状语从句;it在此题中表示时间; It’s + 时间名词+ when…；It’s + 时间状语+that… 这是一个强调句;本题中的evening为时间名词,所以应选B;本题第一个空填which, 引导的是一个定语从句,修饰先行词the village; 第二个空是强调句,所以选that,“是在这个村庄发生了地震”;It’s no wonder that…为固定句型,意思是“难怪…”;。
it作形式主语和形式宾语用法
it作形式主语和形式宾语用法2009-09-21 09:58:41| 分类：study | 标签：|字号大中小订阅一、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 ...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：①It + 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。
)②It + be +名词词组+ doing / that ….e.g. It is no good telling lies.(撒谎没好处。
)It is a pity that you didn’t go to see the film yesterda y.(你昨天没看成那部电影真遗憾。
it作主语的用法
it作主语的用法IT作主语的用法在英语中，IT是一个非常常见的代词，它通常用来指代事物或概念。
在句子中，IT可以被用作主语，从而起到引导整个句子的作用。
本文将详细介绍IT作主语的用法。
一、基本用法1. IT + BE动词最基本的IT作主语的用法是与BE动词连用。
这种结构通常表示某种状态或情况。
例如：It is raining outside.（外面正在下雨。
）It was nice to meet you.（很高兴见到你。
）It will be a busy day tomorrow.（明天会很忙碌。
）2. IT + 动词不定式当IT作为形式主语时，后面跟着一个动词不定式，通常表示期望、计划或建议等。
例如：It is important to study hard.（努力学习很重要。
）It is necessary to finish the project on time.（按时完成项目是必要的。
）It is better to ask for help when you need it.（需要帮助时最好寻求帮助。
）3. IT + 名词/形容词/副词从句当IT作为形式主语时，后面跟着一个名词、形容词或副词从句，通常表示某种情况或状态。
例如：It is a fact that smoking is harmful to health.（吸烟对健康有害是事实。
）It is clear that he doesn't want to talk about it.（显然他不想讨论这个问题。
）It is likely that she will come to the party tonight.（她很可能会来参加今晚的聚会。
）二、进阶用法1. IT + 句子IT作为主语时，后面可以跟一个完整的句子。
这种结构通常表示一种情况或状态。
例如：It seems that he is not interested in the job.（看起来他对这份工作不感兴趣。
It作形式主语和形式宾语的用法详解
新希望英语语法精讲------"It〞作形式主语和形式宾语"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用法，是英语学习的主要语法工程之一。
无论是单项选择，还是完行填空，it 用法始终是反复考察的重、热点之一。
现将it在特殊句型中作形式主语和形式宾语用法，进展如下归纳分析，以供学习参考。
一、 It 用作形式主语当不定式〔短语〕、动名词〔短语〕或从句在*个句子中作主语时，为保持句子构造前后平衡，防止头重脚轻，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 e. (谁要来还不确定。
) 〔It为who will e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 is a pity that you didn’t go to see the film yesterday. (你昨天没看成那部电影真遗憾。
“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。
“It”作形式主语和形式宾语的用法详解
新希望英语语法精讲------“It”作形式主语和形式宾语“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用法，是英语学习的主要语法项目之一。
无论是单项选择，还是完行填空，it 用法始终是反复考查的重、热点之一。
现将it在特殊句型中作形式主语和形式宾语用法，进行如下归纳分析，以供学习参考。
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：①It + 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。
)②It + be +名词词组+ doing / that ….e.g. It is no good telling lies. (撒谎没好处。
)It is a pity that you didn’t go to see the film yesterday. (你昨天没看成那部电影真遗憾。
it作形式主语
㈠ it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toobey 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 rubbishdumps）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）◆It be + 形容词+ for sb. to do sth.与It be + 形容词+of sb. todo sth.：如果句型中的形容词描述的是sb.的品质、品格，在逻辑上可以作sb.的表语，则sb.前应用介词of，否则就用for。
①It’s necessary for us to use a short-wave radio to pick up theprogrammes.我们用一台短波收音机收听这些节目是必要的。
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。
it做形式主语的主语从句结构
it做形式主语的主语从句结构在学习英语时，我们常会碰到“it”作为形式主语的句子，这种结构其实不难掌握，但初学者可能会觉得有点拗口。
今天，我们就来深入了解一下“it”作为形式主语的用法吧！1. 什么是形式主语？首先，我们需要搞清楚什么是形式主语。
简单来说，形式主语就是“it”在句子中起到的作用。
其实，“it”本身并不指代任何具体的事物，而是为了让句子结构更清晰、更自然。
大家可以把它当作一个“占位符”，直到我们真正找到句子的“真正主角”。
1.1 形式主语的基本结构我们可以用一个简单的例子来理解：“It is important to finish your homework.” 在这个句子里，“it”就是形式主语，而真正的主语是“to finish your homework”。
换句话说，我们用“it”来引导读者注意到后面的内容。
1.2 为什么要用形式主语？那为什么不用直接说“Finishing your homework is important”呢？其实，形式主语让句子听起来更自然、更容易理解，尤其是当真正的主语比较长或复杂时。
这就像是给句子一个“热身”时间，让读者在进入正题之前，先对句子的结构有个大致的了解。
2. 形式主语的用法接下来，我们来看看一些常见的情况，什么时候需要用形式主语“it”呢？2.1 当从句作为主语时当句子的主语是一个从句时，我们通常会用“it”来代替。
比如说：“It is clear that he is very talented.” 在这个例子中，“It”替代了“that he is very talented”这个从句，让句子更流畅、更易于理解。
2.2 当不定式或动名词作为主语时同样的，当句子的主语是一个不定式（to do something）或动名词（doing something）时，我们也会用“it”作为形式主语。
例如：“It is difficult to master a new language.” 这里，“It”替代了“to master a new language”，使得句子结构更加简洁明了。
形式主语it的用法
形式主语it的用法
当主语部分太长时为了句子平衡采用it作形式主语，所谓形式是指句子的真正主语将在句子末段出现。
it作形式主语代替主语从句时，形式主语it没有具体的含义，只是帮助把真正的主语移到句子后面去，使句子显得平稳一些。
此时，主语从句可以用从属连词that引导，也可以用连接代词或连接副词引导。
1
形式主语是动词不定式的一种，它也是逻辑主语，可以把它归类到逻辑主语的第一种（不定式的逻辑主语）用作宾语的不定式，用作目的状语，用作结果状语的不定式都是属于不定式的大概念里面的。
2
主语，是执行句子的行为或动作的主体，如“我写字”中的“我”，就是主语，它做出“写”这个动作。
“写”则是谓语，用来修饰主语，而“字”是接受谓语“写”这个动作的对象，它因此被称为宾语，有的语法书也称它为“客体”或“受体”。
it 作形式主语
it 作形式主语在英语中，形式主语是一种特殊的语法结构，用作主语的一些替代词，代表了整个句子所述的主题。
而在中文中，形式主语则是一种更为广泛的语法现象，它可用于各种歧义性较强的语境中，以代替一些具体的实物或抽象事物，承担起整个句子的主语，从而让句子的意思更加清晰明了。
以下是关于“it 作形式主语”的详细解释。
一、it 的用法it 是一种代词，在英语中，它最常用于对事物或概念进行代名。
在口语或书面语中，人们很少使用 it 作为主语或宾语来表示具体的对象，而通常用于表达抽象概念或无法明确指称的事物。
例如：2. It’s important to be on time. （准时很重要。
）4. It is necessary to study hard if you want to pass the exam. （如果你想通过考试，就必须努力学习。
）在这些例子中，it 代表着一个抽象或无法具体指称的对象，即“下雨了”、“准时很重要”、“似乎没有人在家”等，因此可以说 it 是这些句子的形式主语。
在中文中，it 的用法也十分普遍，尤其是在翻译英文时，我们常常会遇到需要使用形式主语 it 的情况。
以下是其中几个常见的用法。
1. 表示时间在英语中，常常使用 it 作为形式主语来表示时间的流逝。
例如：It’s been a long time since we last saw each other. （自从上一次见面以来，好久好久了。
）It took me two hours to finish my homework. （我花了两个小时才完成作业。
）这里的 it 表示的是时间的流逝、经过和耗费。
2. 表示距离类似地，it 也可作为形式主语，表示距离的远近或耗费的时间。
例如：3. 表示天气或自然现象It’s snowing heavily. （下大雪了。
）It’s a beautiful day today. （今天天气真好。
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浅谈it作形式主语的用法
It作形式主语，放到句首，常见句型有：
1. It + be + 形容词+ 主语从句，如：
It is uncertain whether he can come to Jenny’s birthday party or not.
2. It + be + 名词词组+ 主语从句，这类名词有：a fact, a pity, a shame, an honor,
a question等，如：
It is a pity that you missed the exciting football match.
It remains a question whether he will come or not.
3. It + be + 过去分词+ 主语从句，这类过去分词有：announced, believed, expected, hoped, decided, reported, said, shown等，如：
It is reported that 16 people were killed in the earthquake.
It is not decided who will give the operation to the patient.
4. It + 不及物动词(seem, appear, happen等) + 主语从句, 这类不及物动词有：appear, happen, seem等，如：
It seemed that he didn’t tell the truth.
It happened that I was out when he called.
5. It + be + 形容词（修饰事情）+ for sb. + to do
这类句型常用形容词easy, difficult, hard, important, possible, wise等，
It is necessary for the young to master two foreign language.
It is unwise to give the children whatever they want.
6. It + be + 形容词（形容人的心理品质,性格特征）+ of sb. + to do，这类句型常用形容词kind, nice stupid, clever, foolish, polite, impolite, silly, selfish等。
It is very kind of you to help me with the work.
=You are kind to help me.
It seemed selfish of him not to share his dictionary with others.
=He seemed selfish not to share his dictionary with others.
7. It + be +名词词组+ to do，如：
It is not a good habit to stay up too late.
8. It + be + 名词或形容词+ doing，这类名词和形容词常常是：good, no good, no use, a waste of, useless, senseless等，如：
It is a waste of time talking to her any more.
It is no use arguing about the matter with him.
9. It + take ( sb. )+ 时间（金钱）+ to do，如：
It took the workers almost three years to finish building the dam.
It will take a whole day to get to the top of the mountain on foot.。