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初中二年级英语

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  • 句型转换
    句型转换。
    1. We should exercise to keep healthy. (改为同义句)
    We should exercise to _________ healthy.
    2. To eat a balanced diet is very important.(改为同义句)
    _________ very important _________ eat a balanced diet.
    3. She has a sore throat. (改为同义句)
    There is something _________ _________ her throat.
    4. There is a lot of milk in the bottle.(改为同义句)
    There is _________ _________  milk in the bottle.
    本题信息:2012年同步题英语句型转换难度一般 来源:张琳贺
  • 本题答案
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本试题 “句型转换。1. We should exercise to keep healthy. (改为同义句)We should exercise to _________ healthy.2. To eat a balanced diet is very important.(...” 主要考查您对

形容词

实义动词

介词

it 的用法

等考点的理解。关于这些考点您可以点击下面的选项卡查看详细档案。
  • 形容词
  • 实义动词
  • 介词
  • it 的用法
形容词
简称adj.或a,形容词用来修饰名词或代词,表示人或事物的性质、状态,和特征的程度好坏与否,形容词在句中作定语,表语,宾语补足语。
她是一个好学生,她学习努力。She is a good student, and she works hard.
这辆自行车很贵。This bike is expensive.
对不起,我现在很忙。I am sorry, I'm busy now.
你为这次会议做好准备了吗? Have you got everything ready for the meeting?
形容词的语法功能:
一、作定语
He is the greatest writer alive.他是依然健在的伟大的作家。
Somewone else has done it.别人已经做了这事。
二、作补语
形容词做主语补足语和宾语补足语时,可以表示其现状、状态,也可以表示某一动作的结果,并常用在表示“认为,看待”的动词如believe,prove,consider等候。例如:
The news made her sad.这消息使他感到非常悲伤。
Don't marry young.不要早婚。
三、作状语
形容词或形容词短语可作状语,形容词作状语时,可以看作是“being+形容词”结构的省略,可表示时间、原因、条件、方式、强调或伴随状况等意义。例如:
Enthusiastic,they are co-operative.热心的时候他们是很合作的。
Rich or poor, young or old, we all have problems.不管是穷人还是富人,不管是年轻人还是老人,我们都有问题。
四、做表语
The ship was adrift on unknown seas.那艘船在陌生的海域漂流。
五、做主语
Old and young joined the discussion.
Rich or poor meant the same to him.作感叹语
Very good!Say it again.
Stupid!He must be crasy.

形容词的几个特殊用法:
most 同形容词连用而不用 the, 表示 " 极,很,非常, 十分"。
It's most dangerous to be here. 在这儿太危险。
I cannot do it, it's most difficult. 我干不了这件事,太难了。

"The+形容词比较级..., the+形容词比较级..." 表示 " 越... 就越..."。
The more you study, the more you know. 你学的越多, 就知道的越多。
The more I have, the more I want. 我越有就越想要有。
The more, the better. 越多越好。

" 形容词比较级 + and + 形容词比较级 ", 表示 " 越来越... "。
It's getting hotter and hotter. 天气越来越热了.
It's pity he is getting poorer and poorer. 真可怜他越来越穷了。
The computer is cheaper and cheaper. 计算机越来越便宜。
The more and more people focus on the meeting next year. 越来越多的人关注明年的会议。

主语+谓语(系动词)+as+形容词原形+as+从句。表示两者对比相同。
This box is as big as mine. 这个盒子和我的一样大。
This coat is as cheap as that one. 这件衣服同那件衣服一样便宜。
 I study English as hard as my brother. 我同我兄弟一样学习努力。

the + 形容词 表示某种人。
He always helps the poor. 他经常帮助穷人。
I like to have a talk with the young. 我喜欢同年轻人谈话。
The rich sometimes complain their empty life. 富人有时抱怨他们空虚的生活。
The police led the old man across the street. 警察领老人横过马路。

以-ly结尾的形容词
1) 大部分形容词加-ly可构成副词。但 friendly,deadly,lovely,lonely,likely,lively,brotherly,仍为形容词。
改错:(错) She sang lovely.             (错) He spoke to me very friendly.
   (对) Her singing was lovely.  (对) He spoke to me in a very friendly way.
2)有些以-ly 结尾的词既为形容词,也为副词。
daily,weekly,monthly,yearly,early
The Times is a daily paper.
The Times is published daily.

too+adj.+to句型   “太…而不能”
  He is too young to go to school.
 =He isn’t old enough to go to school.
 =He is so young that he can’t go to school.


形容词的位置:
1.形容词一般放在名词前作定语  
单个形容词修饰名词时,一般要放在名词的前面。它们的前面常常带有冠词、形容词性物主代词、指示代词、数词等。例如:  
a red flower一朵红花
an interesting story一个有趣的故事  
six blind men 六个盲人
my own house我自己的房子
如果有两个或两个以上的形容词修饰一个名词时,则由它们和被修饰的名词之间的密切程度而定,越密切的形容词越靠近名词。
如果几个形容词的密切程度差不多则按音节少的形容词放在前面,音节多的形容词放在后面。  
2.当形容词所修饰的词是由some,any,every,no等构成的不定代词时,形容词必须置于名词之后。例如:  
    She has something new to tell me.她有一些新的情况告诉我。  
    I have nothing important to do today.今天我没有重要的工作要做。  
    Do you know anybody else here?这儿你还有认识的人吗?  
3.形容词后面有介词短语或不定式短语时,形容词必须置于名词之后。例如:  
    It is a problem difficult to work out.这是一道难以解决的问题。  
    Edison is a student difficult to teach.爱迪生是个很难教的学生。  
    This is a kind of flowers easy to grow.这是一种易栽的花。  
4.用 and 或 or 连接起来的两个形容词作定语时一般把它们放在被修饰的名词后面。起进一步解释的作用。例如:  
    All people,young or old,should be strict with themselves.  
    所有的人,无论老少,都应该严格要求自己。  
    We are building a new school, modern and super.  
    我们正在建一所现代化的高档次的新型学校。  
    All countries, rich and poor, should help one another. 所有的国家,无论穷富都应该互相帮助。  
5.有少数形容词,如enough和possible,既可置于所修饰的名词前面也可以置于它所修饰的名词之后。例如:   
Do you have enough time(time enough)to prepare?你有足够的时间做准备吗?   
Maybe it will be a possible chance(chance possible)for you.或许它将成为一次可能的机遇。
6.有些形容词,置于名词之前与之后,含义不尽相同。例如:  
the writer present 出席的作者  
the present writer 现在的作者
7.表示长,宽,高,深,及年龄的形容词,应放在相应的名词之后。
This river is about 100 metres wide.
The building is more than 50 metres tall.
 He is less than 40 years old.
8. enough修饰名词时,在名词前后都可以。
They said that they had enough food.= They said that they had food enough.
 enough 修饰形容词和副词,位于其后。
 He is old enough to join the army.
 He isn’t old enough to go to school.
9.形容词else通常放在疑问代词,疑问副词或不定代词后
 what/who/where/when/when else
 something/anything/nothing…else
 What else did you do?
 Do you have anything else to say?
10.由两个或两个以上的词组成的形容词词组修饰名词时须放在名词之后。
This is the book easy to read.
这是一本容易读的书。


形容词知识拓展:
名词化的形容词:
有些形容词可以和定冠词连用,表示一类人或事物,这时,它相当于一个名词,可作主语或宾语;
表示一类人时,看作复数,表示一类事物时,通常看作单数。
Robin Hooh(罗宾汉) hated the rich and loved the poor.
The old are taken good  care of in American.
the+形容词,常见的短语有:
the old/the young/the sick/the white/
the black/the rich/the poor/the dead(死者)

形似副词的形容词:
以-ly结尾的词通常是副词,但是下列词为形容词。
friendly  lonely (孤独的) ;lively (活着的);lovely(可爱的)

复合形容词的类型:
(1)名词+过去分词  man-made satellite 人造卫星
(2)形容词+现在分词  a good-looking man
(3)形容词+名词  second-hand cars
(4)数词+名词-ed   three-legged chairs三条腿的椅子
(5)数词+名词  400- metre race
(6)副词+现在分词  hard-working students
(7)副词+过去分词  well-known writers
(8)形容词+形容词  a dark-red jacket
(9)形容词+过去分词  ready-made clothes 成品服装

含有形容词的常用句型:
(1) It’s+adj. of sb. to do sth.
(good/ kind/nice/polite/clever/foolish… )
It’s very kind of you to help me.
(2) It’s +adj. for sb. to do sth.
(difficult/easy/hard/dangerous/usefulinteresting/important…)
It’s important for us to learn English well.
(3)下列形容词后常跟动词不定式
 表示情感或情绪的形容词:glad,pleased,sorry,sad,afraid,thankful…
 I'm glad to see you.
表示能力,意志或推测的形容词:ready,able,sure,certain…
 I’m sorry to hear that.

某些现在分词和过去分词可作形容词
the moving story 令人感动的故事
a moved boy   一个被感动的男孩
a frightened child 一个被吓到的孩子
a frightening film 一个恐怖电影
实意动词:
即行为动词,表示动作的动词。实义动词与系动词是相对的,能独立用作谓语。
它分为及物动词和不及物动词两种:
及物动词是指后面要求有直接宾语的动词;
不及物动词指后面不需要跟宾语的动词。

实意动词使用方法:
及物动词
后面必须跟宾语意义才完整的实义动词,叫做及物动词(transitive verb)。如:
I believe that the committee will consider our suggestion.我相信委员会将会考虑我们的建议。
“How long can I keep the book ?”Harry asked.哈里问:“这本书我可以借多久?”
Dr. Bethune set us a good example. 白求恩大夫给我们树立了好榜样。
Crude oil contains many useful substances.原油含有许多有用的物质。

不及物动词
本身意义完整后面不须跟宾语的实义动词,叫做不及物动词(intransitive verb)。如:
Birds fly.鸟会飞。
It happened in June 1932.这件事发生于一九三二年六月。
My watch stopped.我的表停了。
She spoke at the meeting yesterday evening. 她在昨天晚上的会上发了言。

兼作及物动词和不及物动词
英语里有不少实义动词可以兼作及物动词和不及物动词。这样的动词又有两种不同的情况
a)兼作及物动词和不及物动词时,意义不变。试比较:
Shall I begin at once?我可以立刻开始吗?(begin作不及物动词)
She began working as a librarian after she left school.她毕业后当图书馆管理员。(began作及物动词)
When did they leave Chicago?他们是什么时候离开芝加哥的?(leave 作及物动词)
They left last week. 他们是上周离开的。(left 作不及物动词)
b)兼作及物动词和不及物动词时,有时意义不尽相同。如:
Wash your hands before meals.饭前要洗手。
Does this cloth wash well? 这布经得起洗吗?


英汉实意动词用法比较:
与汉语的比较,有时英语动词的及物和不及物的用法,与汉语的用法不一样,请注意下列两种情况:
a)有的动词在英语里只能用作不及物动词,而汉语则可用作及物动词,如arrive到达,agree同意,listen听。英语里这些动词后面常接介词。如:
We arrived at the railway station at noon.
我们于中午到达火车站。(at不能省去)
(比较:We reached the railway station at noon.)
Everybody listened to the lecture with great interest.
每个人都很有兴趣地听讲课。(to不可省去)
(比较:We all heard the lecture.)
Do they agree to the plan?他们同意这个计划吗?(to不可省去)

b)有的动词在英语里能用作及物动词,而在汉语里则不能用作及物动词,如serve为…服务。
Our children are taught to serve the people wholeheartedly.
我们的儿童被教以全心全意为人民服务
用于be动词之后,实义动词之前。

 实意动词的用法:
肯定句:
主语+动词过去式+其它
否定句:
主语+助动词didn‘t+动词原型+其他
一般过去式:
Did+主语+动词原型+其他


介词:
是一种用来表示词与词、词与句之间的关系的虚词,在句中不能单独作句子成分。
介词后面一般有名词代词或相当于名词的其他词类,短语或从句作它的宾语。
介词的分类:
(1)表示时间,处所:从 自 自从 于 打 到 往 在 当 朝 向 顺着 沿着 随着
(2)表示方式:按 照 按照 依 依照 本着 经过 通过 根据 以 凭
(3)表示目的:为 为了 为着
(4)表示原因:因 由于 因为
(5)表示对象,范围:对 对于 把 向 跟 与 同 给 关于
(6)表示排除:除 除了 除去 除非
(7)表示被动:被 叫 让 给
(8)表示比较:比 和 同
上述介词中的“着,了,过”是语素,不是动态助词。

介词at, in, on的区别: 
1. 表示时间,注意以下用法:
(1) 表示时间的某一点、某一时刻或年龄等用 at。如:
I get up at six in the morning. 我早上六点钟起床。
He got married at the age of 25. 他 25 岁结婚。
(2) 泛指一般意义的上午、下午或晚上以及月或年等较长的时间,一般用 in。如:
We watch TV in the evening. 我们晚上看电视。
He went to Japan in 1946. 他于 1946 去了日本。
(3) 若表示星期几或某一特定的日期,则用 on。如:
He left here on the fifth of May. 他于 5 月 5 日离开这儿。

2. 表示地点、场所、位置等,注意以下用法:
(1) 表示某一点位置,用 at。如:
We live at No 87 Beijing Road. 我们住在北京路 87 号。
The hospital is at the end of the street. 医院在这条街的尽头。
与名词所有格连用表示地点,也用 at。如:
at my sister’s 在我姐姐家  at the doctor’s 在医务室
(2) 表示空间或范围,用 in。如:
What’s in the box? 这盒子里有什么?
He lives in Paris with his wife. 他同他妻子住在巴黎。
但有时两者可换用。如:
The meeting was held at [in] the hotel. 会议在宾馆举行。
(3) at 与 in 的另一个区别是:at 用于指较小的地方,而 in 用于指较大的地方。如:
in Shanghai 在上海    at the station 在车站
但是,大与小是相对的,有时随着说话者的着眼点不同,大地方也可能用 at(比如把一个大地方看作一个点时)。如:
Our plane refuelled at London. 我们的飞机在伦敦加油。
We stopped for an hour at Moscow on our way to Paris. 我们在去巴黎的途中在莫斯科停了 1 个小时。
(4) 介词 on 用于地点,主要指在某物的表面。如:
What’s on the table? 桌上有什么?
There’s a wallet lying on the ground. 地上有个钱包。
注:在少数搭配中,也用介词 on。如:
He works on a farm. 他在农场工作。

3. 在某些搭配中,三者的区别与英国英语和美国英语有关:
in the street (英) / on the street (美) 在街上
in the road (英) / on the road (美) 在路上
in the team (英) / on the team (美) 在这个队
at the weekend (英) / on the weekend (美) 在周末
at weekends (英) / on weekends (美) 在周末
4. 有时三者的差别与搭配习惯和用法有关:
in bed / on the bed 在床上
in the tree (多指树外之物) / on the tree (多指树本身之物) 在树上

介词besides,but,except的用法区别:
 1. 三者都可表示“除外”,但 besides 表示一种累加关系,意指“除了什么之外,还有……”;
而 except 或 but 则表示一种排除关系,意指“除了什么之外,不再有……”。如:
Besides his wife,his daughter also went to see him. 除他妻子外,他女儿也去看过他(即妻子女儿都去看过他)。
Nobody went to see him except [but] his wife. 除他妻子外,没有一个人看过他(即只有他妻子去看过他)。
注:在否定句中,besides 也表示“除……之外不再有…… ”,与but, except 同义。如:
No one passed the exam besides [except] Jim. 除吉姆外,没一个人通过考试。

2. 关于 but 与 except:
(1) 两者都可表示“除……外不再有……”,但含义上略有差别:
but侧重指意义的几乎完整性,而 except 则侧重指后面除去的部分。比较:
All are here but one. 除一个人都到了。
All are here except one. 还有一个人没到。
(2) 在现代英语中,but 的介词用法十分有限,一般说来,它只能用在下列词语之后:
① no, no one, nobody, nothing, nowhere 等
② any, anyone, anybody, anything, anywhere 等
③ every, everyone, everybody, everything, everywhere 等
④ all, none 等
⑤ who, what, where 等
Everyone knows it but you. 除你之外大家都知道。
I haven’t told anybody but you. 除你之外,我没告诉任何人。
No one but he [him] showed much interest in it. 除他之外没有一个人对此有很大兴趣。
一般说来,若没有出现上述词汇,就不宜使用介词 but,否则可能造成错句。但是 except 却没有以上限制。比较:
正:The window is never opened except in summer. 除夏天外,这扇窗户从不打开。
误:The window is never opened but in summer.
(3) but 一定不能用于句首,except 通常不用于句首:
除我之外每个人都累了。
正:Everyone is tired but (except) me.
正:Everyone but (except) me is tired.
误:But (Except) me, everyone is tired.
注:except for 可用于句首,表示 except 的意思:
正:Except for me, everyone is tired.

3. 关于 except 与 except for:
except 主要用来谈论同类的东西,而 except for 则主要用来谈论不同类的东西,有时含有惋惜之意。如:
All compositions are well written except yours. 除了你的作文外,其他的作文都写得很好。
His composition is good except for a few spelling mistakes. 他的作文写得不错,只是有几处拼写错误。
注:若用于句首,则 except for 与 except 同义(但 except 通常不用于句首)。

4. 关于 except for 与 but for:
except for 主要表示排除,but for 主要表示一种虚拟条件(与虚拟语气连用)。如:
Except for me, everyone passed the exam. 除了我之外,大家都通过了考试。
But for my help, she would not have passed the exam. 若不是我的帮助,她就不会通过考试。
But for the atmosphere plants would die. 如果没有大气,植物就会死亡。
5. besides 除用作介词外,还用作副词,其意为“此外”、“而且”,可用于分句句首(通常用逗号隔开)或句尾。如:
I don’t want to go; besides, I’m too tired. 我不想去,而且我也太累了。
This car belongs to Smith, and he has two others besides. 这部车是史密斯的,此外他还有两部。


介词的用法口诀:

早、午、晚要用inat黎明、午夜、点与分。

年、月、年月、季节、周,阳光、灯、影、衣、冒in

将来时态in。。。以后,小处at大处in

有形with无形by,语言、单位、材料in

特征、方面与方式,心情成语惯用in

介词atto表方向,攻击、位置、恶、善分。

日子、日期、年月日,星期加上早、午、晚,

收音、农场、值日on,关于、基础、靠、着论。

着、罢、出售、偷、公、假,故意、支付、相反,准。

特定时日和“一……就”,on后常接动名词。

年、月、日加早、午、晚,of之前onin

步行、驴、马、玩笑oncabcarriage则用in

at山脚、门口、在当前,速、温、日落、价、核心。

工具、和、同随with,具有、独立、就、原因。

就……来说宾译主,对、有、方状、表细分。

海、陆、空、车、偶、被by,单数、人类knowtoman

thisthattomorrowyesterdaynextlastone

接年、月、季、星期、周,介词省略已习惯。

overunder正上下,abovebelow则不然,

若与数量词连用,混合使用亦无关。‘

beyond超出、无、不能,against靠着,对与反。

besidesexcept分内外,among之内along沿。

同类比较except,加for异类记心间。

原状becauseof,、owingtodueto表语形容词

under后接修、建中,offrom物、化分。

beforeafter表一点,agolater表一段。

before能接完成时,ago过去极有限。

since以来during间,since时态多变换。

与之相比beside,除了lastbutone

复不定for、找、价、原,对、给、段、去、为、作、赞。

快到、对、向towards,工、学、军、城、北、上、南。

butfor否定用虚拟,复合介词待后言。

ing型由于鉴,除了除外与包合。

之后、关于、在。。。。。。方面,有关介词须记全。

into外表位置,山、水、国界to在前。


“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。如:
 It’s no use crying over spilt milk.
5.It takes sb.+一段时间+to do sth. 表示“做某事花费某人多长时间”。如:
It took us half an hour to ride to the town by the sea.
6.It is +及物动词的过去分词+that从句
此句型中常见的及物动词的过去分词有:said, told, known, reported, recorded, thought, believed, considered等。如:
It is reported that the Russian President will visit China next week.
7.It +不及物动词+that从句
此句型中不及物动词常见的有:seem, happen, appear, matter等。如:
 It seems that there will be a heavy snow tomorrow.
 It happened that I met my good friends in the museum yesterday.
8.强调句型:It is+被强调部分+that/who从句
在使用强调句型时要注意,指人时可以用who或that,其它情况一律用that。如:
 It was under the bed that my brother hid the ball this morning.
 It is Mr Bell who/that often comes and looks after the old man.
9.It is/has been+一段时间+since从句。如:
It is /has been three years since we saw each other last.
10.It is (high) time that sb. did sth.
该句型表示“某人现在该做某事了”,从句常用过去时(虚拟语气)说明现在应该做的事情。如:
 It’s six o’clock.It is high time that we went home now.

It 常用的固定搭配:
1. make it
(1)在口语当中相当于succeed,表示:成功、做到、说定、赶上、及时到达
例  It's hard to make it to the top in show business.
(2)在口语中相当于fix the date for,表示“约定好时间”
例  —Shall we meet next week?
—OK. We just make it next Saturday.
2. as it is
(1)相当于in fact,in reality表示“事实上,实际情况是……”
例  We had planed to finish the task today,but as it is we probably won't finish it until next week.
(2)相当于方式状语从句,表示“照原样”
例  Leave the table as it is.
3. as it were
相当于as one might say,that is to say,表示“也就是说,可以说,换句话说”
例  He is,as it were,a modern Sherlock Holmes.
4. if it weren't for…/if it hadn't been for…
用来引导虚拟语气,相当于without,or but for,表示“如果不是……,要不是……”
例  If it weren't for Tom,I wouldn't be alive today.
5. that's it
(1)相当于That's all. That's so much. 表示“至此为止,没有别的了”
例  You can have one more sweet,and that's it.
(2)相当于 That's right.表示“对啦”
例  — I guess the key to the problem is thechoice “A”
—That's it.
6. catch it
在口语中,相当于be punished/scolded for doing sth. wrong. 表示“因做错事而挨骂,受责备,受批评,受惩罚”
例  We'll really catch it form our teacher if we're late for class again.
7. have it
(1)相当于say,insist表示“说,主张,表明,硬说”
例  Rumour has it that they are getting divorced.
(2)相当于get to know something,表示“了解,知道,获悉”
例  I had it from John that she was going abroad.
8. have what it takes
在口语中,相当于be well qualified for,表示“具有成功的条件”
例  You can take it from me that your daughter has what it takes to be a star.
9. so it seems / appears.
10. Keep at it!(Don't give up!)
相当于go on,表示“继续做,不放弃”
例  My teacher asked me to keep at it.
11. Go it!(Go on!)拼命干,莽撞
12. Now you have done it!(You have done sth. wrong.)
13. Now you'll catch it!(You'll be punished.)
14. As it happened,…
在口语中,相当于it's a pity that…,表示“真不凑巧,真遗憾”
例  As it happened,they were out.
15. As it turned out,…
在口语中,相当于it was found to be in the end,表示“最后被证明是”
例  As it turned out,his statement was false.
16. Such as it is(they are)
在口语中,相当于although it may not be worth much,表示“虽然没有多大价值”
例  You can borrow my exam notebook,such as it is.
17. Take it/things easy.
相当于Don't worry or don't hurry. 用来劝告别人,表示“不要慌,别担心,存住气”
例  Take it easy! He will do it well.
18. Take it from me.
在口语中,相当于believe me what I say.表示“请相信我的话,我敢担保”
例  You can take it from me that he will make it this time.
19. For what it is worth…
在口语中,相当于although I'm not sure it's of value,表示“不管其价值如何”
例  Here is the article I promise you,for what it's worth.
20. Worth it
在口语中,相当于useful,表示“有好处,值得做”
例  Don't hesitate about it! It's worth it.
21. Believe it or not.表示“信不信由你”
例  Believe it or not,Tom is getting married to Mary next Sunday.
22. Take it or leave it. v. 要么接受要么放弃
例  That is my last offer. You can take it or leave it.
23. It all depends/that all depends
在口语中,相当于it hasn't been decided yet,表示“那得看情况,还没有定下来”
例  —Are you going to the countryside for holiday?
—It/That all depends.
24. It's up to sb.
在口语中,相当于it's decided by sb. 表示“由……决定,由……负责,取决于……”
例  —Shall we go out for dinner?
—It's up to you.

it用法小结:
It用作实词
表达以下概念:
指代前文提到的事物,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。

一、it 作人称代词的用法
1. 指事物
作为人称代词,it 可以除人以外的一切事物或动物。如:
I dropped my watch and it broke. 我把手表掉在地上摔坏了。
It’s hard work, but I enjoy it. 工作很辛苦,可是我乐意干。
“Where is the dog?” “It’s in the bedroom. ” “狗在哪?”“在卧室里”。
2. 指人
it 指人主要用于指不性别不明的婴儿或用于确认某人的身份。如:
Is it a boy or a girl? 是男孩还是女孩?
There is a knock on the door. It must be the postman. 有人在敲门,一定是邮递员。
【说明】在答语中,常用来指本人,如说 It’s me。
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, nothing等。如:
“What’s this?” “It’s a new machine. ” “这是什么?”“是一种新机器”。
Nothing is wrong, is it? 没出什么问题,是吗?

二、it 作非人称代词的用法
1. 基本用法
it 作非人称代词的用法,主要用于指时间、距离、价值、天气、气候及温度等自然现象。如:
It’s too late to go there now. 现在去那儿已经太迟了。
It rained all day yesterday. 昨天下了一天的雨。
It can get very hot here. 这里有时会很热。
2. 用于某些句型
It’s time for sth. 该做某事了。
It’s time to do sth. 该做某事的时候了。
It’s time for sb to do sth. 某人该干某事了。
It’s (about / high) time + that-从句. 某人该做某事了。(从句谓语用过去式,有时也用“should+动词原形”)
It’s first (second) time + that-从句. 某人第几次干某事。(从句谓语用现在完成时)
It’s + 时间段 + since-从句. 自从……有一段时间了。
It’s + 时间段 + before-从句. 过多长的时间才……

三、it用作形式主语
1. 基本用法
当不定式、动名词、从句等复杂成分用作句子主语时,为保持句子平衡,通常把真正的主语放在句末,而在句首使用形式主语it。如:
It’s very important to remember this. 记住这一点很重要。
It’s hard work climbing mountains. 爬山是费劲的事。
It’s unknown when he will come. 他什么时候来还不知道。
2. 用作形式主语的的重要句型
(1) It + be + adj. for (of) sb to do sth 某人做某事……
It is hard for him to make up his mind. 他很难下定决心。
It was foolish of her to say such a thing. 她说那样的话,真是太蠢了。
【说明】介词 of 与 for 的区别是:
of 用于指某人的性格、属性、特征等,介词for表示对象,意为“对……来说” 。
(2) It takes sb + 时间段 + to do sth. 某人做某事花了……时间
It takes years to master a new language. 要花多年的时间才能掌握一门新的语言。
【说明】此句型可以有以下多变种变体:It took me an hour to write the letter.
=The letter took me an hour (to write). =I took an hour to write the letter. 我写这封信花了一个小时
(3) It is up to sb to do sth. 该由某人做某事
It’s up to you to to make the choice. 得由你来作选择。
(4) it look (seem, appear, happen, occur) that [as if]… 似乎……
It seemed as though he didn’t recognize me. 他似乎没认出我来。
It happened that I was out when he called. 他打电话时我碰巧不在家。
(5) If it were not for… / If it hadn’t been for… 若不是因为……
If it were not for their help, we couldn’t have got over the difficulties. 要不是他们帮助,这些困难我们不克服不了的。

四、it用作形式宾语
1. 基本用法
当不定式、动名词、从句等复杂成分用作宾语且其后跟有宾语补足语时,通常会在宾语补足语前使用形式宾语,而将真正的宾语移至句末。
其基本结构为“动词+it+宾语补足语+不定式(动名词或从句)”。如:
I find it difficult to do the job well. 我发现做好这件事不容易。
I think it best that you should stay here. 我认为你最好住这儿。
We think it no use complaining. 我们认为抱怨是没有用的。
2. 用作形式宾语的几个特殊结构
(1) 动词+ it + that-从句。如:
I like it that you came. 你来了,我很高兴。
I take it (that) he will come on time. 我认为他会准时来的。
You can put it that it was arranged before. 你可以说这是以前安排的。
Rumor has it that the defence minister will soon resign. 据传闻,国防部长不久就要辞职。
【说明】能用于此结构的动词不多,常见的有 have, take, put, like 等。
(2) 动词 + it + when (if)-从句。如:
I dislike it when you whistle. 我不爱听你吹口哨。
We really appreciate it when she offered to help. 她来帮忙了,我们十分感激。
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,好就太好了。
【说明】能用于此结构的动词不多,常见的有 enjoy, hate, love, like, dislike, appreciate, prefer 等。
(3) 动词 + prep + it + that-从句。如:
See to it that you’re not late again. 注意千万不要再迟到。
Look to it that this doesn’t happen again. 注意不要再发生这种事。
You may rely on it that he’ll come to meet you. 你放心,他会来接你的。
I can’t answer for it that he will come. 我不能保证他会来。
【说明】能用于此结构的动词不多,常见的有see to, look to, insist on, stick to, depend on, answer for 等。
(4) 动词 + it + 介词短语+ that-从句。如:
I owe it to you that I am still alive. 多亏有你我才仍然活着。
I took it for granted that he would help us. 我认为他会帮助我们的。
【说明】能用于此结构的动词不多,常见的有take it for granted, bring it to sb’s attention, owe it to sb 等。

it在强调句中的使用
It is+被强调部分+that(who)+其他
在使用强调句型时需注意以下几点:
1. 请注意强调句型的特殊疑问句 
2. 在强调原因状语从句时,只能强调由because所引导的从句。
3. 在强调not … until结构时必须把not与until一起放到被强调的位置上。
4. 注意强调句型与定语从句的区别。
5. 不管被强调部分是单数还是复数,其前一律用It is / It was,而不能用They are / There were之类的。
6. 被强调部分是指人时,被强调部分后可用that / who,被强调部分指物时,被强调部分后只能用that。
7. 被强调部分是指时间或地点时,被强调部分后通常用that,一般不用when,where之类的。例:
It is I who am right. 是我对。
It was you that were wrong. 是你错了。
It was in the Japan that he died. 他是死于日本。
It was yesterday that he got married. 他是昨天结婚的。
It was a computer that he bought last week. 他上个星期买的是一台电脑。
Where was it that she lived? 她是住在什么地方?
When was it that he left for Japan? 他是什么时候离开去日本的?
Who is it that teaches you English? 是谁教你们英语?