it 做形式主语和however 用法

不管however以何种形式出现，它都不外乎以下两种用法。

1. 用作副词

(1) 表示让步：意为“无论如何”“不管怎样”，用来修饰形容词或副词，

其词序为：however+形容词或副词+主语+谓语。这样用的however其实具有连词的功能，用以引导让步状语从句。如：

however much he eats, he never gets fat. 不管他吃多少，他永远吃不胖。

用于此用法时，请注意以下几点：

①此用法属however所有用法中最重要的考点，同学们务请引起高度重视。

②这样用的 however 与 no matter how 大致同义。如：

People always want more, however [no matter how] rich they are. 人总是富了还想再富。

however [No matter how] hard I worked, she was never satisfied. 无论我多么努力地工作，她从来没满意过。

③有时从句谓语可用情态动词。如：

Don’t laugh, however funny it may be. 无论多么有趣也不要笑。

I’ll try to finish it in time, however hard it may be. 无论多么难，我也要按时完成。

④“however＋形容词或副词＋主语＋谓语”有时可以有所省略。如：

I refuse, however favorable the conditions. 不管条件如何有利，我都不干。(conditions 后省去了are)

I’d rather have a room of my own, however small (it is), than share a room. 无论房间多么小，我宁愿一个人住一间，而不愿意与别人合住一个房间。

A grammar rule, however true (it is), is useless unless it can be understood. 一条语法规则，不管如何正确，除非能懂，否则毫无用处。

(2) 表示转折：尤其用于谈及一个既成事实时，表示转折，其意为“可是”“仍然”等。可放在句首、句中或句末，通常用逗号与句子其他成分隔开。如：

My father, however, did not agree. 但是，我父亲不同意。

My room is small; however, it’s comfortable. 我的房间很小，但却很舒服。

He said that it was so; he was mistaken, however. 他说情况如此，可是他错了。注：however不能像 but(但是)那样直接连接两个句子(注意正句中的标点符号)。如：

我们都已尽了最大的努力，不过我们还是输了。.

正：We all tried our best, but we lost the game.

正：We all tried our best; however, we lost the game.

正：We all tried our best. however, we lost the game.

(3) 表示惊奇或强调：相当于how ever的用法，其意为“究竟怎样，到底以什么方式”。如：however did you get here without a car? 没有汽车你究竟是怎样来的呢?

No matter +疑问词或者疑问词-ever 含义为“无论……都, 不管……都”。他们引导让步状语从句，并且可以互换。

It作形式主语常见句型

动词不定式，动名词或主语从句作主语时，通常把它们放在谓语动词前，而用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 honour，

a question等，如：

It’s 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 + for sb.）+ 动词不定式

这类句型常用形容词easy, difficult, hard, important, possible，wise等作表语，有时候为了强调不定式动作的执行者，常在不定式前加for sb，如：

It’s necessary for the young to master two foreign language.

It is unwise to give the children whatever they want.

这类形容词有：easy, difficult, hard, important, possible，wise

6. It + be + 形容词 + of sb. + 动词不定式，这类形容词常是表示心理品质,性格特征的形容词，如：kind, nice stupid, clever, foolish, polite, impolite, silly, selfish, considerate等。某人和这些形容词可以构成主系表结构。如：It’s 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 + 动词不定式，如：

It is not a good habit to stay up too late.

8. It + be + 名词或形容词 + 动名词，这类名词和形容词常常是：good, no good, no use, a waste of, useless, senseless等，如：

It’s 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）+ 动词不定式，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.

同位语从句是用来解释说明某一名词内容或实质的句子。他所修饰的名词为同位词，在同位语从句中，that 只起连接作用，不作任何句子成分，that 无意义。同位语从句的引导词不能省略.

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) rember 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 Engl ish 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

It作形式主语和形式宾语，虽然是我们高中就学过的语法点，但在考研英语题型中，无论是在阅读还是翻译，常会考查该知识点。 一.it作形式主语。 英语中不定式、动名词、主语从句在作主语时主语往往显得很长，使整个句子看上去有点头重脚轻，这样就借助“it”来作形式上的主语，而把真正的主语移到句子后边去，使全句结构上前后平衡。“it”并无实际意义。It之后的谓语部分，可以是be+形容词，be+名词(词组)，或be+过去分词等。 it 作形式主语，主要分为下列三种情况：不定式作主语、动名词作主语和名词从句作主语。具体分析如下： 一、不定式作真正主语主要用于下列句型： 1. It + is/was + adj./n.+ to do sth. A.名词作表语。主要有a pity, a pleasure, an idea等。 It is a good idea to think this way. 这样考虑问题是个好办法 除be外，其他动词也有跟名词的情况。例如： It seems a pity to waste the food. 浪费这些食物真可惜。 B. 形容词或形容词短语作表语。分两种情况： 1.下列形容词；kind,good,nice,clever,wrong,right,foolish,wise,unwise,stupid,rude,careless,cruel,brave ,naughty,polite,selfish等词作表语时，不定式前常可加一个由of引起的短语，来说明不定式指的是谁的情况。形容词表示不定式逻辑主语的特征，即形容词用来描述不定式行为者的性格、品行等。例如： It was foolish of you to leave school.你中途退学，真是傻瓜。 2. 其他形容词作表语，常见的形容词有：necessary, hard，important, difficult, easy, possible，common等。 It is necessary to learn English. 需要注意的是：动词不定式作主语，一般情况下用it作形式主语，而把动词不定式（从句）放在后面。也可以直接用不定式作主语。例如： It is wrong to tell lies. = To tell lies is wrong. 撒谎是不对的。 但在疑问句和感叹句中，只能用it作形式主语。例如：

It作形式主语常见用法

It作形式主语常见句型 有时为避免句子头重脚轻，常用形式主语it代替主语从句作形式主语放于句首，而把主语从句置于句末。主语从句后的谓语动词一般用单数形式。常用句型如下：1. 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： It 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。 It 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。 2. 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： It is quite certain that he will be at the meeting. 他将出席会议是无疑的。 It is surprising that he came late to school this morning. 他今天早上迟到真令人惊讶。 It 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. 3. It ＋seem／appear／happen的适当形式＋that从句。 It seems that there is a big waste pipe coming down from the town. It appeared that he was calm, but inside his heart was beating wildly with fear. 4. It + be + 过去分词+ 主语从句

初中英语语法：it用作形式主语的用法

初中英语语法：it用作形式主语的用法 一、基本用法 当不定式、动名词、从句等用作主语时，避免头重脚轻，通常在句首使用形式主语it，而把真正的主语放在句子末尾： Is it necessary to tell his father everything? 有必要把这个切都告诉他父亲吗? It’s no good sitting up too late. 熬夜没有好处。 It is quite clear that he has read the book. 很显然，他读过这本书。 It doesn’t matter what he says. 他说什么没关系。 二、几种特殊的形式主语 (1) 用作动词look, seem, appear, happen, occur, follow等的主语(后接that从句或as if从句)： It seems as if it is going to rain. 看来要下雨了。 It seems that he knows everything. 他好像什么都知道。 It (so) happened that I had no money with me. 碰巧我没带钱。 From this witness it follows that he must be guilty. 根据该证人的证词判断，他一定有罪。 (2) 当系表结构后接有if 或when引出的状语从句时，通常在系表结构前使用形式主语表示说话人对某情况的看法： It was a great surprise to me when he did a thing like that. 他这样做使我很吃惊。

It”作形式主语和形式宾语用法详解

新希望英语语法精讲------“I t”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： 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 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。) ③ It + be + 过去分词 + that …. 该句型常见动词有：say, hope, think, suppose, expect, report, know, believe, decide, etc. e.g. 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。) ④ It + seems / appears / happens等不及物动词 + that ….

it做形式主语的用法大全

It作形式主语常见句型 动词不定式，动名词或主语从句作主语时，通常把它们放在谓语动词前，而用it作形式主语，放到句首，常见句型有： 1. It + be + 形容词（important, impolite.necessary. easy, difficult.....）+ 动词不定式(to do sth..........) It is impolite to keep others waiting. It is important to arrive on time. 2. It + be + 形容词(important, impolite.necessary. easy, difficult....).+主语从句，如： It is important that you must arrive on time.. 2. In fact is a hard job for the police to keep order in an important football match. (2001 上海) A. this B. that C. there D. it 3. is a fact that English is being accepted as an international language. (NMET1995) A. There B. This C. That D. It 4. Is necessary to take off our shoes when we enter the lab? (MET88) A. everyone B. this C. her D. it 5. ________ will take you a lot of time to find him in the crowd. A. It B. I C. We D. They 8. ___________ is known to all that Shenzhou VI Launched

It作形式主语的几大基本句型

“It”作形式主语的几大基本句型 2011-06-07 22:27:53| 分类：语法归纳| 标签：|字号大中小订阅 ◇It’s +形容词/名词+that +从句 It is necessary that you train yourself before the walk. It is important that you have your own support team. It was a pity that he lost the game. It’s a pity that you missed the exciting football match. ◇It’s +形容词+(for sb) +to do sth It is difficult to walk through eight country parks. It is useful to have support teams. It is important for him to finish it in ten hours. It is necessary for people to learn team spirit. 特别提醒： ☆该句型的否定结构为It’s +形容词+(for sb) +not +to do sth It is very important not to give them too much food. (7B 100) It is very polite not to speak loudly in public. ☆该句型有时可以与It is + adj. + that从句的句型互换使用，意思不变。如：It is necessary for you to train yourself before the walk. = It is necessary that you will train yourself before the walk. ◇It’s +名词+to do sth It’s everyone’s duty to obey the law. It is not a good habit to stay up too late. As a student, it is bad manners to come late to class. It is my turn to clean the blackboard.

it做形式主语的19个句型教学提纲

i t做形式主语的19 个句型

It作形式主语常见句型 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。 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. = 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 ...+(should) do 该句型和上一个同属一个句型。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。 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……）”。 6. It is suggested ( ordered, required ... ) that ... +(should) do 该句型和上一个同属一个句型。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……）”。 7. It is a pity ( a shame ... ) that ...

It 作形式主语的三种句型

It 作形式主语的三种句型 【热身训练】 Ⅰ. 单项选择 ( ) 1. — Is it to talk with her? — Yes. She is not always friendly to others. A. kind B. easily C. meaningful D. tough ( ) 2. It is meaningful us action to protect our Earth. A. of; to take B. for; to take C. of; taking D. for; taking Ⅱ. 按要求完成下列各题。(第3~4题翻译句子；第5题改写同义句) 3. 加入他们做一些志愿者工作很有趣。 4. 对孩子们来说，在马路上踢足球是危险的。 5. It is important that we should understand our parents. is important us our parents. 【融会贯通】 It is + adj. + that从句 用法简介 该句型中that从句在句中作主语，it作形式主语。这个句型常用来说明对某事的感受。句型意为“某人做某事是……”。 典型例句 It’s necessary that you wash your hands before meals. 你饭前洗手是必要的。 It’s + adj. + (not) to do sth. 用法简介 这是动词不定式短语作主语的最常用句型。动词不定式短语作主语时，常用it 作形式主语，而将真正的主语(动词不定式短语)后置，以保持句子的平衡。句型意为“(不)做某事是……”。 典型例句 It’s important to learn a foreign language. 学一门外语是重要的。 It is very polite not to speak loudly in public. 在公共场合不大声说话是非常礼貌的。 It is + adj. + for / of sb. (not) to do sth. 用法简介 这是I t’s + adj. + (not) to do sth.的延伸句型。当动词不定式短语作主语，且其含有自己的逻辑主语时，在动词不定式短语之前用介词for或of引出其逻辑主语。 典型例句 It is very easy for me to finish the work. 完成这项工作对我来说是很容易的。 It’s very kind of you to help me. 你能帮我，真好。

It作形式主语常见用法

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雅思考试it作形式主语的用法 雅思考试中，it这个词的用法还是很变化多端的。考虑到它在雅思考试中的高出现率，今天天道雅思论坛小编就来为同学们做一个雅思辅导，说一说it的用法。以下是今天的精彩讲解。 雅思考试，先来了解一下it作形式主语的用法： (一)什么是形式主语 作为形式主语的it并无实际语义，是为满足语法上的需要，避免句子头重脚轻，它代替的是句子的逻辑主语。 (二)形式主语it所在的句型类别 1、作不定式的形式主语 (1)句型 It;is;+;a;pity/a;pleasure;+;to;do;sth. It;is;+;wrong/right/wise/cruel/naughty/selfish;+;of;sb.;+;to;do;sth. It;is;+;necessary/hard/important/difficult/possible/common;+;for;sb.;+;to;do;sth. (2)雅思范文写作实例 A.;Beyond;this,;it;is;also;of;paramount;importance;to;use;theaters;and;museums;as;the;“social;classroom”;of;culture;and;history;education. B.;I;think;it;is;by;no;means;pointless,;in;any;way,;to;try;to;keep;traditions;alive;wit h;technology.;(Cambridge;3,;P162,;Task;2) C.;It;is;difficult;to;say;who;has;the;right;to;judge;whether;children;working;is;“wron g”;or;“valuable”.;(Cambridge;3,;P164,;Task;2) D.;…,;it;is;important;to;remember;that;children;need;to;d evelop;skills;other;than;inte llectual;ones,;and;…(Cambridge;3,;P168,;Task;2) E.;Finally,;I;think;that;it;is;also;important;to;remember;that;children;need;to;relax;a s;well;as;work,;…(Cambridge;3,;P168,;Task;2)

It作形式主语常见用法.doc

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) rember 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做形式主语用法大全

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it作形式主语和形式宾语

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it作形式主语或形式宾语的用法

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They haven’t made it known where they are to hold the conference. 他们还没宣布会议在哪里开。 几种特殊的形式宾语it 1. enjoy, like, dislike, love, hate, prefer, appreciate等动词后接 if 从句或 when 从句，通常应先在动词后接 it 作形式宾语。如： She won’t like it if you arrive late. 她不喜欢你迟到。 He hates it when people use his bike. 他讨厌别人用他的自行车。 I hate it if you say such things in public. 我讨厌你在大庭广众之下说那样的事。 I’d prefer it if I didn’t have to do so much work.要是我不必做那么多工作，那就太好了。 I would appreciate it very much if you would help me with it. 如果你能帮助我做这事，我会十分感激。

it做形式主语的个句型

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。 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. = 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 ...+(should) do 该句型和上一个同属一个句型。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。 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……）”。 6. It is suggested ( ordered, required ... ) that ... +(should) do 该句型和上一个同属一个句型。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……）”。 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. 这种事竟然发生在你们班上，真是遗憾！It is a pity that he is ill. 他生病了，真遗憾！ 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……”。 9. It is the first ( second … ) time that … 该句型要和上一个句型区别开来。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 替换，常译为“是第一（二）……次……”。 It is the first time I have been here. = This is the first time I have been here. 10. 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。 11. 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……”。 12. It be ... before ...