It句型归纳
It句型归纳
It 句型归纳1．It is ＋adj．(＋for sb．／sth．) ＋to do sth．用于此句型的形容词有：easy，hard，difficult，possible，important，impossible，necessary，good，bad，exciting，interesting，surprising等。
如：It is necessary to change your job．It was very hard for them to walk such a long way inthe snow．2．It is ＋n．(＋for sb．／sth．) ＋to do sth．用于此句型的名词有：pity, shame, pleasure, one’s duty, one’sjob, fun, joy, good manners, bad manners等。
如：It is a pity for you to have missed such a wonderfulplay．It is bad manners for the young to take up the seatsfor the old．3．It is ＋adj．＋of sb．＋to do sth．此句型中的形容词主要描述某人的品德、特征。
能用于该句型的形容词有：kind, nice, wise,silly, polite, impolite, friendly, foolish, clever等。
如：How silly it was of you to give up such a goodchance！It is friendly of the family to try to make me feelat home in their house．4．It is ＋adj．（＋n．）＋doing sth．此句型中的形容词和名词常见的有：no／little use, no／much good,useless等。
It的用法及典型句型归纳. 个人总结
It的用法及典型句型归纳一、人称代词it的最基本用法是作代词，主要指刚提到的事物，想法，以避免重复;也可以指性别不明或性别被认为是不重要的人或动物；未指明但谈话双方都明白的事情或情况。
①They watched the train until it disappeared in the distance.②Is this your dog？No, it isn’t.③I hate it when people talk with a full mouth.．二、.非人称代词.it有时并不指具体的东西而泛指天气、时间、日期、距离、价值、度量、温度、环境等：It is a lovely day, isn’t it? // It was nearly midnight when she came back.It is April First today. // It is some 3000 kilometers from A to B.It is three dollars. // Today it is 30 degrees centigrade.三、作形式主语，替代主语从句，动词不定式，或动名词短语1.作形式主语替代主语从句⑴It is clear ( obvious，true，possible，certain....) that＂┅清楚的（显然的，真的，可能的,肯定的．．．）＂⑵It is important ( necessary，right，strange，natural...) that + (should ) do (虚拟语气)┅是重要的(必要的,对的,奇怪的,自然的┅)⑶It is said (reported/ learned/believed/thought/known/told/hoped.....) that= sb / sth is said (reported/ believed /thought…) to do( to be doing/ to have done) sth＂据说（据报道，据悉．．．）＂。
it的9种主要句式
it的9种主要句式it句型是初中英语中使用频率较多的重点句型之一，为了便于同学们搞好中考复习，现将常见有关it的主要句式归纳如下：1.“It is time for……〞表示“是……时候了〞。
句中介词for后接名词或代词作宾语。
如：It’s time for school.是上学的时候了。
2.“It’s time to do sth.〞表示“是做某事的时候了〞。
此句常与上句替换使用。
如：It is time for us to have lunch.=It is time for our lunch.是我们吃午饭的时候了。
3.在“It seems……〞句中，seem是不及物动词，常作系动词用，有“好似、似乎〞的意思，后面可跟动词不定式、形容词作表语，也可跟从句。
如：It seemed that nobody knew anything about the matter.看来没有人了解这件事。
4.“It’s one’s turn to do sth.〞表示“轮到某人做某事了〞。
如：It’s your turn to play ping-pong.该轮到你打乒乓球了。
5.“It is+形容词+to do sth.〞表示“做某事怎么样〞。
其中it作形式主语，替代后面的不定式to do sth.(真正主语)。
如：It is easy to speak English. 说英语很简单。
6.“It is+形容词+for X.+to do sth.〞意为“对某人来说做某事怎么样〞。
这种结构中的形容词常常是easy，difficult，hard，important，necessary，quick等，这些形容词常与事物的特征有关。
如：It is quite difficult for us to find out who broke the windows.对我们来说，查明是谁打破了窗户是相当难的。
7.“It is+形容词+of X.+to do sth.〞表示“某人做某事怎样〞。
it句型归纳
It 可指代单数、不可数的物，上文提到的事，时间，金钱，距离，天气。
有时也可以指人、婴儿I: It 作形式主语的句型：1.it + be + adj. ( kind, wise, careless, clever…) + of sb to doIt is wise of him to make such a decision.2.It + be +adj.( easy, safe, common, important, hard….) for sb to doIt is very dangerous for children to play with fire.3. It is useless/ no use/ no good… doingIt is no use arguing with him further.4..It + be+ v-ed (reported, said, believed,….)that 从句…It is said that Tom has been back from abroad.句型中的V-ed 为（表建议suggested, advised, proposed，命令ordered, commanded，要求demanded, requested, insisted）that从句中的谓语should + V原形/be done)It is suggested that the meeting (should) be put off..5.It +be + n.( a pity/ a shame/ a fact, good news….) that …It is good news that Tu Youyou won the Nobel prize.6.It takes sb some time to do sth.It took many people many years to build the Great Wall.II: it 作形式宾语的句型：Sb + ( find/believe/feel/ consider/ think/ make ..) it + adj. / n. to do / thatWe think it our duty to clean our classroom every day.They found it hard that they would finish their work in two weeks.III: IT 引导的时间句型1.It + is +一段时间+ since引导的时间状语从句该句型中从句一般用过去时态，句意为“自从。
It常用句型大盘点
It常用句型大盘点“It” 用法及其句型和固定搭配，是英语语法的重点、难点，又是近几年考试的热点，因此在复习中应给予足够的重视。
现将it用法归纳如下：1. It is + 被强调部分+ that ...【说明】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、表语或状语。
强调的主语如果是人，that可以换成who。
如果把这种句型结构It is / was... that /who... 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。
【举例】It was I who / that met Jim in the street.(强调主语)It was in the street that I met Jim. (强调状语)It was Jim who / that I met in the street. (强调宾语)It is a chief engineer that he becomes now. 他现在担任的是总工程师（强调表语）2. It is not until + 被强调部分+ that ...【说明】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。
【举例】It was not until I got home that my mother went to bed.= M y mother didn’t go to bed until I got home.=Not until I got home did my mother go to bed.3. It’s no use / good doing sth. 做某事没有用。
【举例】I t’s no use/good crying over spilt milk.= Crying over spilt milk is no use / good.4. It’s a waste of time doing sth. 浪费时间做某事。
It句型用法详解
It句型用法详解研究1991-2005年的高考试卷中可以发现含it的句型年年考到。
可见it句型的重要性和使用的普遍性。
现根据其用法特点归纳为２０个句型．1. It +be + 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，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。
It was about 600 years ago that the first clock with a face and an hour hand was made.It was they that (who ) cleaned the classroom yesterday.It was in the street that I met her father.It was neither you nor he that is willing to go to the Great Wall．It was he as well as his classmates who has ever been to Suzhou．(强调含有either．．．or．．．，neither．．．nor．．．，not only．．．but also．．．，as wellas，not．．．but．．．等词组所构成的句子)强调句型还可以怎样设计？这种提法并不是要把我们弄糊涂，而是要培养我们对该句型的应变能力。
万变不离其宗，要对强调句型产生免疫力，就要对该句型各种可能的考法烂熟于心。
下面我们谈谈强调句的考法设计。
1.1.疑问法：疑问法可分为一般疑问法和特殊疑问法两种。
主要是通过改变语序后将it和that混在一块儿，使考生对结构无法辨认而出错。
这形式可考查考生的纠错能力。
一般疑问句：①. Is _______ student_______ was caught smoking in the classroom?A. it that, thatB. that it, itC. it it, thatD. it which, that特殊疑问句：②. _______ he got up?A. When was that itB. Was it when thatC. When was it thatD. Was that when it③. Where________ he picked the wallet?④. _______ student________ you referred to?结论：一要注意语序；二要注意词序（特殊疑问词要置于句首），三要注意特殊疑问词的选用，疑问代词还是疑问副词。
it句型归纳和例句
it句型归纳和例句it句型是英语语法中的一个重要句型，用于指代前文或上下文中的某事物或概念。
它通常由一个形容词或介词短语修饰，并且可以作为主语、宾语或介词宾语出现。
以下是对it句型的详细解释和相关例句。
1. 作为主语当it作为主语时，它经常用来表示天气、时间、环境或情况等抽象的事物。
在这种情况下，it的作用是引导一个描述句子的主语，使语句更加具体。
例如：It is raining outside.（外面正在下雨。
）It is Friday today.（今天是星期五。
）It is difficult to make a decision.（做出决定很困难。
）2. 作为宾语当it作为宾语时，它通常出现在及物动词、介词短语和形容词后面，表示句子中所描述的事物。
例如：I think it is important to learn English.（我认为学习英语很重要。
）She always wears a hat to protect it from the sun.（她总是戴着帽子来保护自己不被太阳晒伤。
）He found it difficult to concentrate on his work.（他发现很难集中精力工作。
）3. 作为介词宾语当it作为介词宾语时，通常作为一个具体的对象或概念被指代，并出现在介词后面。
例如：I'm thinking about it.（我正在考虑这件事。
）She is good at it.（她很擅长于此。
）I'm not used to it.（我不习惯这种情况。
）此外，it句型还可以与各种被动语态，感官动词和情态动词结合使用，形成更加复杂的句子结构。
例如：It was built in 1920.（它建立于1920年。
）I can't see it clearly.（我看不清楚它。
）It must be done as soon as possible.（这必须尽快完成。
It句型归纳最全总结
It句型归纳最全总结It句型归纳总结I。
It作形式主语的句型1.It is adj (kind。
wise。
careless。
XXX.) of sb to do sth.For example: It is wise of him to make such a XXX wise.2.It is adj (easy。
safe。
common。
normal。
) for sb to do sth.If adj is important。
necessary。
natural。
possible。
strange。
vital。
essential。
etc。
it can be changed to a clause。
and the clause should use should + verb.For example: It'XXX for children to play with fire。
Children playing with fire is very dangerous.It is important for us to learn English well。
It is importantthat we (should) learn English well.3.It is V-ed (reported。
believed。
said。
XXX.) that clause.In this sentence pattern。
if V-ed is reported。
believed。
said。
etc。
it is often translated as "据报道"。
"据认为"。
"据说"。
If V-ed is suggested。
ordered。
demanded。
insisted。
etc。
which means "suggested"。
It 构成的20句常用句型归纳
It 构成的20句常用句型归纳【句型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，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。
【例】It was about 600 years ago that the first clock with a face and an hour hand was made.【例】It was they that (who ) cleaned the classroom yesterday.【例】It was in the street that I met her father.【句型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。
【例】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.【句型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形式主语句型
“it”在英语中经常用作形式主语，尤其是在主语从句中。
形式主语用于表示主语从句，即一个句子作为主语，而“it”是这个句子的形式主语。
以下是几个使用“it”作为形式主语的常见句型：
1. It is + 形容词+ that + 主语从句
例如：It is clear that he has made a mistake.
解释：在这个句型中，“it”是形式主语，“that”后的句子是真正的主语。
2. It is + 名词+ that + 主语从句
例如：It is a fact that the earth is round.
解释：这个句型与上一个相似，但形容词被替换为名词。
3. It + 动词+ 主语从句
例如：It happened that he was late for the meeting.
解释：在这个句型中，“it”是形式主语，动词是主语从句的谓语。
4. It + be + 时间/距离+ before + 主语从句
例如：It will be two years before we meet again.
解释：这个句型用于表示在某个时间或距离之后会发生某事。
5. It is/was + 被强调部分+ that + 主语从句
例如：It was yesterday that he met his friend.
解释：这个句型用于强调某个时间或部分。
这些只是使用“it”作为形式主语的一些常见句型。
在英语中，还有其他更复杂或特定的用法。
It句型归纳最全总结
It 句型归纳总结I．It 作形式主语的句型①It + be + adj (kind , wise , careless, clever…) + of sb to do sthEg: It is wise of him to make such a decision.他做出这样的决定是明智的。
②It + be + adj(easy , safe , common , normal …) + for sb to do sth该句型中adj若为important, necessary, natural, possible, strange, vital, essential等可改为从句,从句用should+动词原形。
.Eg: It’s very dangerous for children to play with fire.It is important for us to learn English well. (= It is important that we (should) learn English well.)③It + be +V-ed( reported, believed, said, suggeste d…) + that 从句该句型中：⑴若V-ed为reported, believed, said等常译为“据报道”，“据认为”，“据说”。
⑵若V-ed为suggested, ordered, demanded, insisted等表示“建议”,“命令”的词，从句要用虚拟语气(should)+动词原形。
Eg: It is suggested that the book (should) be revised.It’s said that Tom has been back from abroad. (=Tom is said to have been back from abroad.)④It + be + n (a pity, a shame, a fact , good new s…) + that 从句:该句型中，从句一般用(should) + 动词原形，表示出乎意料，常译为＂竟然＂。
It 常用句型归纳
It 常用句型归纳一、It is +形容词+that clauseIt is obvious that he is round and tall like a tree.It is strange that he should be so rude to his parents.二、It is +形容词+(for sb.) to do sth.It is wise (of you) to keep silent.It is necessay for you to put all your heart into study now.三、It is +被强调部分+ that clauseIt is in the park that he was robbed lat week.四、It is a pity + that clauseIt is a pity that he should lose the game this time.五、It is time + that clauseIt is time that we went to bed.六、It is the first time + that clauseIt is the first time that I have been to America.七、It is +一段时间+since…It is(has been) two decades since we graduated from school.八、It is +一段时间+ before…It was three hours before he got there.九、It is said +that clauseIt is said that our team won the game.十、It is no good/use/+doing。
it的句型归纳清单-高三英语一轮复习
It的句型归纳一、it 作形式主语的句型（is都可以换成was或其他变形）It is + adj. + that…1.It is obvious that……. 是显而易见的2.It is true that………是真实的3.It is natural that……..是自然的4.It is surprising that……..是令人惊讶的5.It is good that…….是好的6.It is wonderful that………是很棒的7.It is funny that……. 是有趣的8.It is certain that………..是肯定的9.It is probable that………可能的10.It is likely that………可能的11.It is possible that………可能的It is +名词+that…12.It is no wonder that.. 难怪…..13.It is an honor that…很荣幸….14.It is a good thing that…….是好事15.It is a pity that…很遗憾…..16.It is no surprise that…….不令人惊奇It is + 过去分词+ that….17.It is said that.. 据说…..18.It is reported that…据报道….19.It is thought that …普遍认为….20.It is expected that…期盼…..21.It is decided that.. 决定….22.It is announced that.. 宣布….23.It is arranged that…安排….It +动词或动词短语+ that…（所有加s都可以换成其他时态。
）24.It seems that…看起来…..25.It happens that…碰巧….26.It matters that…….关键；….起作用27.It appears that…看起来似乎….28.It turns out that…后来证明…；事实证明….29.It proves that…后来证明…；事实证明….30.It occurs that…碰巧….31.It seems as if…看起来似乎….32.It looks as if…看起来似乎….33.It looks as though…看起来好像….34.It occurs to sb. that…. 某人突然想起…..35.It es to sb. that…某人突然想出….36.It strikes sb. that.. 某人突然想出….37.It hits sb. that…某人突然想出….38.It is well known that…. 众所周知….39.It is well acknowledged that…众所周知….其他句型40.It is no use doing …做…没用41.It is useless doing sth…做…没用42.It is no good doing sth…做…没用43.It takes sb. some time to do sth…. 花费某人多少时间做…..44.It is high time that…是做…. 的时候45.It is the first time that…第一次做……46.It was the second time that…第二次做…..47.I t is +时间段+ since + 从句（一般过去时）自从….以来有多久48.It has been + 时间段+ since +从句（一般过去时）自从….以来有多久49.It + be + 时间段+ before+从句（时态遵守主将从现或前后一致）（肯定）过了多久才….（否定）没过多久就…50.It be + 被强调部分+that……51.It is + adj. + for sb. + to do sth…对某人来说做….怎么样52.It is + adj. + of sb. + to do sth…对某人来说做….怎么样二、it 作形式宾语的句型1.take it that…. 认为….；想…2.hate it when…. 讨厌….3.like it when…喜欢….4.can’t help it if…如果…,我也没办法5.appreciate it if…如果…将感激不尽6.I don’t mind it if…如果…我不介意7.see to it that…确保…;务必….8.count on it that…相信…..9.As someone puts it, ….. 像某人说的那样10.If you don’t feel like it, …. 如果不喜欢,就….11.When it es to….., ….. 当谈到…..12.主语+think/believe/ suppose/consider/feel/ make/keep/…. + it + useless/ nogood / no use….+ doing sth. 某人认为……没用13.主语+ think/believe/ suppose/consider/feel/ make/keep/…. + it + adj./ n. +for/of sb. + to do sth. 某人认为……怎样。
it句型归纳总结大全
it句型归纳总结大全"it"句型是英语中常见的一种句型结构，通常用来强调或者指代特定的事物或情况。
下面是对"it"句型的归纳总结：1. 强调句型：It is (was) + 被强调的部分 + that/who + 其余部分。
例，It is the book that I want to read.（我想读的就是这本书。
）。
例，It was Mary who broke the window.（打破窗户的是玛丽。
）。
2. 虚主语句型：It + be + 形容词 + to do.例，It is important to learn English well.（学好英语很重要。
）。
3. 虚宾句型：It + be + 名词 + to do.例，I find it a pleasure to work with you.（我觉得和你一起工作很愉快。
）。
4. 指代句型：It + be + 形容词 + (for sb.) + to do sth.例，It is easy for me to solve the problem.（对我来说解决这个问题很容易。
）。
5. 天气句型：It + be + adj. + (for sb.) + to do sth.例，It is hot for us to go out.（对我们来说出去很热。
）。
6. 距离句型：It + be + 距离 + to + 地点。
例，It is five kilometers to the station.（离车站还有五公里。
）。
以上是对"it"句型的归纳总结，希望对你有所帮助。
如果你还有其他问题，欢迎继续提问。
it的详细用法
it的用法“It”用法及其句型和固定搭配，是英语语法的重点、难点，又是近几年考试的热点，因此在复习中应给予足够的重视。
It 句型归纳：1． It is ＋adj．(＋for sb．／sth．) ＋ to do sth．用于此句型的形容词有：easy， hard， difficult，possible， important，impossible， necessary， good， bad， exciting， interesting， surprising 等。
如： It is necessary to change your job．It was very hard for them to walk such a long way in the snow．2．It is ＋n．(＋for sb．／sth．) ＋ to do sth．用于此句型的名词有： pity, shame, pleasure, one’s duty, one’s job, fun, joy, good manners, bad manners等。
如：It is a pity for you to have missed such a wonderful play．It is bad manners for the young to take up the seats for the old．3．It is ＋adj．＋of sb．＋to do sth．此句型中的形容词主要描述某人的品德、特征。
能用于该句型的形容词有：kind, nice, wise, silly, polite, impolite, friendly, foolish, clever等。
如：How silly it was of you to give up such a good chance！It is friendly of the family to try to make me feel at home in their house．4．It is ＋adj．（＋n．）＋doing sth．此句型中的形容词和名词常见的有：no／little use, no／much good, useless 等。
It 的 13 个常用句型及其运用!书面表达必备!
It 的13 个常用句型及其运用！书面表达必备！It 的13 个常用句型及其运用it 虽然并不显眼，但只要运用得当，也能在书面表达中发挥出巨大的作用，给人以高大上的感觉。
本文在归纳其常用的句式结构的基础上着眼于在书面表达中如何恰当地运用it 的相关句型，以达到优化句子，增加文章亮点。
01一、it 句型的归纳：( 一) it 作形式主语的 6 个句型句型1. It is + adj. (=of n.) + for sb. to do sth. / that... 某人做某事是……的。
Will it be convenient for you to start work tomorrow? 你明天开始工作方便吗?It is vital /of great significance for students to take regular exercise. = It is vital /of great significance that students should take regular exercise. 定期进行锻炼这对学生来说太重要了。
句型2. It is a shame / pity that... 很遗憾……(1) It is a shame that some students should scribble and litterrandomly on the campus. 一些学生竟然在校园中乱涂乱画，乱扔垃圾，这真是太不应该了。
(2) It is a pity that I cannot go to see the movie on Saturday evening. 很遗憾，周六晚上我没办法陪您去看电影了。
说明： that 引导的从句为主语从句，从句中谓语动词的语气分两种情况：①表述的内容是事实，用陈述语气 , 如例句 (2) ；②若内容表明说话人的一种语气 / 情感则使用虚拟语气 , 如例句 (1) 。
It的用法(超全)
---------------------------------------------------------------最新资料推荐------------------------------------------------------It的用法(超全)用法及其句型和固定搭配，是英语语法的重点、难点，又是近几年考试的热点，因此在复习中应给予足够的重视。
句型归纳：1． It is ＋adj．(＋for sb．／sth．) ＋ to do sth．用于此句型的形容词有：easy， hard， difficult，possible， important， impossible，necessary， good， bad， exciting， interesting， surprising 等。
如：It is necessary to change your job． It was very hard for them to walk such a long way in the snow． 2．It is ＋n．(＋for sb．／sth．) ＋ to do sth．用于此句型的名词有：pity, shame, pleasure, ones duty, ones job, fun, joy, good manners, bad manners 等。
如：It is a pity for you to have missed such a wonderful play． It is bad manners for the young to take up the seats for the old． 3．It is ＋adj．＋of sb．＋to do sth．此句型中的形容词主要描述某人的品德、特征。
能用于该句型的形容词有：1 / 13kind, nice, wise, silly, polite, impolite, friendly, foolish, clever 等。
“It” 重点用法归纳
“It” 重点用法归纳一、it在特定句型中的运用1. It was/will be long(one week/two years ...)+before从句此句型可译为“很久(一周/两年后……)才……”。
如:It was long before he came back.很久以后他才回来。
It will not be long before we meet again. 不久我们就又会见面。
2. It is/has been/was + some time + since从句此句型可译为“自从……以来已经有多长时间了”。
如:It is / has been more than fifty years since the People’s Republic ofChina was founded.中华人民共和国成立已经有五十多年了。
It was three days since he had fallen ill. 他生病已经有三天了。
注意:①如果since从句中的谓语动词为延续性动词时, 应译为“自从不……以来已经有多长时间了”。
如:It is / has been seven years since I taught in this school.我离开这所学校已经有七年了。
②时态的把握:如果主句运用的是一般现在时或现在完成时,那么since 引导的从句用一般过去时;如果主句运用的是一般过去时,那么since引导的从句常用过去完成时。
3. It + be + the +序数词+ time + that从句此句型可译为“是某人第几次做某事了”。
如:It is the first time that I’ve spoken in public.这是我第一次公开发言。
注意:如果主句是一般现在时或一般将来时,从句用现在完成时;如果主句是一般过去时,从句用过去完成时。
4. It +be +具体时间+ when ...此句型可译为“当某事发生时,时间是在……”。
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It 句型归纳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，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。
It was about 600 years ago that the first clock with a face and an hour hand was made. It was they that (who) cleaned the classroom yesterday.It was in the street that I met her father.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 ...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。
记住该句型中的形容词。
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。
译为“据说（据报道/据悉…）”。
It is said that he has come to Beijing.It is reported that another earth satellite has been put into orbit.6.It is suggested (ordered ...) that ...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。
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：常用过去时态表示虚拟；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。
It is (has been) 5 years since his father died.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...”。
It was 5 o’clock when he came here.12.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.13.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 that he met his teacher in the street. 碰巧...It seems that he will be back in a few days. 看来...14.It takes 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.15.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, ( not any good ), no use, ( not any use )。
It is no good learning English without speaking English.16.It does n’t matter whether (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 doesn’t matter if they are old.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.该句型与上一个同属一个句型。
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，如：It is important for her to come to the party.= It is important that she (should) come to the party19.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.（真的病了）It looks as if he were ill. （没有生病）It seemed as if he were dying.20. We think it important to learn a foreign language.该句型中的it 作形式宾语。