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初中三年级英语

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  • 句型转换
    句型转换
    1. At old times, children could neither read nor write. (改为同义句)
    At old times, children could not ___________ read __________ write.
    2. We have another two exams before school finishes. (改为同义句)
    We have __________ exams before school finishes.
    3. Both films are wonderful. (改为否定句)
    __________ film is wonderful.
    4. The radio reports that 300 million people in China have eyesight trouble. (改为同义句)
    __________ __________ __________ 300 million people in China have eyesight trouble.
    5. Jack's grandfather doesn't know how he should use a computer. (改为简单句)
    Jack's grandfather doesn't know how __________ __________ a computer.
    本题信息:2012年同步题英语句型转换难度一般 来源:贺倩(初中英语)
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本试题 “句型转换1. At old times, children could neither read nor write. (改为同义句)At old times, children could not ___________ read __________ write.2. W...” 主要考查您对

序数词

不定代词

形容词的比较级,形容词的最高级

不定式

并列连词

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。
  • 序数词
  • 不定代词
  • 形容词的比较级,形容词的最高级
  • 不定式
  • 并列连词
  • it 的用法
序数词:
是数词的一种,主要在英语语法中讲到,在汉语中表示为“第几”。如:first, second, third, fourth

序数词的读法与写法:
序数词写法:

1 first ;2 second ; 3 third  ;4 fourth ; 5 fifth ;
6 sixth ;7 seventh; 8 eighth;9 ninth ;10 tenth ;
11 eleventh ;12 twelfth ;13; thirteenth ;14 fourteenth;15 fifteenth
16 sixteenth ;17 seventeenth ;18 eighteenth;19 nineteenth;
20 twentieth ;30 thirtieth ;40 fortieth ;50 fiftieth ;60 sixtieth ;70 seventieth;80 eightieth ; 90 ninetieth

多位序词:
由基数词的形式变结尾部分为序数词形式来表示。
one hundred and twenty-first 第一百二十一
one thousand three hundred and twentieth 第一千三百二十
two hundred and fifty-second 第二百五十二

缩写:
有时,序数词可以用缩写形式来表示。主要缩写形式有:
first——1st ;second——2nd ;third——3rd; fourth——4th ;sixth——6th ;twentieth——20th;twenty-third——23rd
其中lst,2nd,3rd为特殊形式,其它的都是阿拉伯数字后加上th。


序数词前不加the的情况:
在英语中,使用序数词时前面要加定冠词 the,但是,在下面的情况下则不加 the:
1.当序数词前有形容词性物主代词或名词所有格修饰时,序数词前不用 the。
Mother was my first teacher in my life.妈妈是我生命中的第一个老师。
Tom is Lily's third boyfriend. 汤姆是莉莉的第三个男朋友。
2.当表达分数时,序数词前不用 the。
One fifth of the students here are from the country. 这儿1/5的学生来自农村。
Three fourths of the students here are from the country. 这儿的3/4的学生来自农村。
3.当表达“又一,再一”时,序数词前不用 the,但可加不定冠词。
Please give me a second chance. 请再给我一次机会。
The poor woman had a third baby. 那个可怜的妇女又生了第三个宝宝。
4.当表达“年月日”时,尤其在朗读时,序数词前要加 the。
He was born on June 6th, 1974. 他出生在1974年6月6日。
5.当序数词在句中作状语时,序数词前不用 the。
Who got there second? 谁第二个到那儿的?
I finished the work first. 我最先完成那项工作。
6. 当表达考试(比赛等)中获得的名次时,序数词前不用 the。
She stands first in her class. 她在班上成绩排名第一。


基数词变序数词的口诀:
基变序,有规律,词尾加上-th。
一,二,三,特殊记,词尾字母t,d,d。
八去t,九除e,ve要用f替,ty将y变成i,th前面有个e。
若是碰到几十几,前用基来后用序。
整十基数变序数,先把ty变成tie,要是遇上两位数,十位基数,个位序,th最后加上去。
或者一,二,三变字体;th从4上起;8加h,9减e;用f 代ve;ty变为tie。

序数词的语法功能及用法:
序数词在句中可作主语、宾语、定语和表语。
The second is what I really need. 第二个是我真正需要的。(作主语)
He choose the second. 他挑选了第二个。(作宾语)
We are to carry out the first plan. 我们将执行第一个计划。(作定语)
She is the second in our class.在我们班她是第二名。(作表语)
注:序数词在使用时,通常前面要加定冠词 the;但是如果序数词前出现不定冠词a或an时,则表示“再—”,“又—”。
We'll go over it a second time. 我们得再念第二遍。
We've tried it three times.Must we try it a fourth time? 我们已经试过三遍了,还必须试一次(第四次)吗?
表示顺序的序数词
只需将基数词放在它所修饰的名词之后即可,不需要添加定冠词。
the first lesson——Lesson One    the fifth page——Page 5(five)
the twenty-first room——Room 21(twenty-one)


不定代词
即不指明代替任何特定名词或形容词的代词。
初中常用不定代词有:
some(something,somebody,someone),any(anything,anybody,anyone), no(nothing,nobody,no one),
every(everything,everybody,everyone,),all,each,both,much,many,(a)little,(a)few,other(s),
another,none,one,either, neither等。一般来讲,修饰不定代词的词要置于其后。

不定代词用法例举:
①一般用于肯定句中的不定代词:some, someone, somebody, something
例如:They can speak some Japanese.
②一般用于否定句、疑问句和条件句中的不定代词:any, anyone, anybody, anything
例如:Is there anyone at home?
③一般用于句中表示否定意义的不定代词:no, no one, nobody, nothing
例如:I have no watch.
There is nothing wrong with the machine.
④不定代词one指代可数名词,既可指人,亦可指物,它可以代替上文中出现的单数可数
名词,指代复数名词时可以用ones。
例如:I do not have a pen, can you lend me one?
I like small cars better than large ones.
⑤none通常只用作名词,在句中作主语、宾语等。意为“没有任何(人或物)”,既可指人,亦可指物。
none后常跟of短语,其后用复数可数名词或不可数名词。
例如:None of them knows the answer to the question.
⑥both, all
both指两个人、物或群体;
all指三个以上的人、物或群体或泛指一切事物。
例如:My parents are both teachers.
           All of my friends are football fans.
⑦every, each
each一般用于指两个或两个以上的人或物,侧重个别;
every用于指三个或三个以上的人或物,侧重全体。而且each所指对象在上下文中已十分明确。
例如:Each student went to see that films. (学生至少二人)
            Every student went to the park.(学生至少三人)        
⑧other, the other, others, the others, another
other具有名词和形容词性质,既可指人,亦可指物。other常与定冠词the连用。
不定冠词an与other连用则组成another。other只作形容词或代词,表示“其他的,别的”,不可单独使用。
例如:Do you have any other questions?
the other作形容词或代词,特指两者中或两部分的另一个或另一部分。
例如:The bookshop is on the other side of the street.
 others相当于“other+名词”,泛指“别的人或物”,只有名词性用法。
例如:Some are planting trees, others are watering them.
the others相当于“the other+名词”,表示“剩下的,其余的”,特指除此之外的全部 人或物。
例如:There are forty-six students in our class. Two of them are foreign, the others are all Chinese.
another作形容词或代词,泛指三个或三个以上不定数目中的“另一个”。
例如:This pen is too expensive, please show me another.
⑨either, neither
either指“两者中的任何一个”;neither指“两者中无一”,具有否定意义。
例如:You can take either half.
Neither of the books is good.
⑩many, much, most
many和much具有名词和形容词的性质,都表示“许多、大量”。
Much一般只能指代或修饰不可数名词,many只能指代或修饰复数可数名词。Most指“大部分、大多数”。
例如:Many boys like playing soccer.
We have much homework to do every day.
Most students think so.
(11)few, a few, little, a little
a few 和a little 意为“少数、少量”,其意义是肯定的。
A few指代或修饰复数形式的可数名词,a little指代或修饰不可数名词。
Few 和little意为“几乎一点没有”,具有否定意义。
例如:He has a few friends here.
Hurry up! There is little time left.


不定代词的用法:
不定代词大都可以代替名词和形容词,在句中作主语、宾语、表语、定语和状语。
位置
不定代词+形容词
不定代词+to do
作主语
Both of them are teachers.他们两人都是教师。
作宾语
I know nothing about this person.我对这个人一无所知。
作表语
This book is too much for a child.这本书对一个小孩来说太难了。
作定语
There is a little water in the glass.玻璃杯里有一些水。
作状语
I can't find my book anywhere.我在任何地方都不能找到我的书。
修饰不定代词的词,一般情况下要后置。
形容词的比较级:
当两种物体之间相互比较时,我们要用形容词或副词的比较级;
当相互比较的物体是三个或三个以上时,我们就要用形容词或副词的最高级。

形容词的比较级和最高级的特殊变化规则:
一、少数单音节词前面加 more-, most- 构成比较级和最高级
tired ---- more tired , most tired
fond ----- more fond , most fond
glad ----- more glad , most glad
bored ---- more bored , most bored
pleased---- more pleased , most pleased

二、不规则变化
good /well------- better ,best
bad/badly/ill------ worse , worst
many/much-------more , most
little ------ less , least
far ---- farther, farthes / firther , furthest
old ---- older , oldest (GA)
    ---- older , oldest / elder , eldest (GB)

三、下列形容词和副词的比较级和最高级有两种形式
cruel----- crueler,  cruelest /more cruel , most cruel
strict---- stricter , strictest /more strict , most strict
often----- oftener , oftenest / more often , most often
friendly------ friendlier , friendliest / more friendly , most friendly
clever----- cleverer, cleverest /  more clever , most clever

四、下列形容词和副词没有比较级和最高(即表示”最高程度”或”绝对状态”的形容词和副词没有比较级和最高级)
empty , wrong , perfect , unique , extreme , excellent , favourite (GB)/ favorite (GA) , true , right , correct , extremely ...


形容词的比较级和最高级用法:
形容词比较等级用法:
 1.没有比较对象时,用原级。
 I have a new computer.
 2.两者比较,程度相同。
 A+系动词+as+adj.+as+B.
 Our school is as beautiful as theirs.
 3.两者比较,程度不同。
 A+系动词+not as+adj.+as+B.
 The weather here is not as hot as that in the south.
 4.A比B更…
 The earth is bigger than the moon.
 5.比较级前可以用much,even,still,far,a lot,a little,a bit,any等修饰。
 Your room is much bigger than mine.
 I’m a little shorter than her.
 6.用比较级可以表示最高级含义:
 John is stronger than any other boy in his class.=John is stronger than any of the other boys.
 两者不属于同一范畴,不能用other.
 Chongqing is bigger than any city in Sichuang.
 7.“比较级+and+比较级”   表示“越来越…”
 China is becoming more and more beautiful.
 Days are getting longer and longer.
 8.用the+比较级,the+比较级  表示”越…就越…”.
 The busier he is, the happier he feels.
 9. Which/Who+is+比较级     A或B?
 A和B哪一个/谁更…?
 Which is better,this one or that one?

 最高级用法:
 表示三者或三者以上的人或物的比较,一个在某方面超过其他两个或多个时,用最高级,结构是
 主语+系动词+the+形容词最高级+of/in短语。
 This story is the most interesting of the three.
 1. one of the+形容词最高级+名词复数
 它的意思是最…之一。
 English is one of the most important languages in the world.
 2. which/who…+is+形容词最高级
 “…最...”
 Which is the heaviest,the horse,the sheep or the elephant?
3.最高级前可以用序数词
 The Yellow River is the second longest river in China.
形容词的比较级和最高级的变化规则:

构成 

 原级

比较级 

最高级 

一般加er,est

 tall

taller 

tallest 

以字母e结尾只
加 r,st

 large

larger 

largest 

以一个辅音字母结尾的
重读闭音节,双写这一辅
音字母后再加er,est

 red

redder 

reddest 

 hot

 hotter

hottest 

 thin

 thinner

thinnest 


以辅音字母+y结尾的词,
将y变为i再加er,est

easy 

 easier

easiest

happy

 happier

happiest 

 ugly

 uglier

ugliest 

 early

 earlier

earliest 

其他双音节词和多
音节词,在词前
加more或most

 interesting

more interesting 

most interesting 


动词不定式:
指由to加上动词原形(而且只能是动词原形)所构成的一种非限定性动词,但在有些情况下to可以省略。
动词不定式在语法功能上可作主语、宾语、宾语补足语、表语、定语和状语。
动词不定式可以作以上各种成分,但它毕竟是动词,所以有动词的属性。
动词不定式及其短语还可以有自己的宾语、状语,虽然动词不定式在语法上没有表面上的直接主语,但它表达的意义是动作,这一动作一定由使动者发出。
这一使动者我们称之为逻辑主语,其形式如下:
时态 主动形式  被动形式 
一般式 (not) to do (not) to be done
完成式 (not) to have done (not) to have been done
进行式 (not) to be doing  
完成进行式 (not) to have been doing  

不定式的用法:
1、不定式作主语
例如:To remember this is very important.
注意:为了避免头重脚轻,在许多情况下,通常都将作主语的不定式置于句子后部,而在句首主语位置使用形式主语it。
例如:It is very important to remember this.
2、不定式作表语
例如:He seems to be ill.
注意:不定式作表语主要有三种情况,一是用于seem, appear, prove等系动词之后的不 定式(尤其是to be),
二是像My job is to sweep the floor. 这样的主语与表语“等价”的情形,
三是表示想法、约定、义务、命令、可能性、命运等,如: 
You are to come when I call.
3、不定式作宾语
例如:I can not afford to buy a car.
注意:
①不定式不仅用作动词的宾语,还可用作个别介词(but, except)的宾语。
例如:I had no choice but to wait.
②当作宾语的不定式后跟有宾语补足语时,通常要用形式宾语it代替不定式,并将真正的宾语不定式置于宾语补足语之后
例如:I find it difficult to learn Japanese well.
4、不定式作宾语补足语
例如:Who taught you to drive?
5、不定式作定语
例如:I have a question to ask you.
注意:有的名词(如way, chance, right等)后用作不定式可换成of doing sth.
如:It is the best way to do (of doing) it.
但是以下名词后接不定式作定语时通常不能换成of doing sth.
attempt  courage  decision  effort  fortune  failure  invitation  wish
6、不定式作状语
例如:I went to France to learn French.
并列连词
主要是用来表示并列关系、选择关系、因果推理关系等。也可用来连接平行的词,词组或分句。

并列连词表示关系及代表实例:
1.表示并列关系
表示并列关系的连词主要含有“和”、“补充”、“增加”等意思。用来表达并列关系的连词有如下几个:
and 和 both...and...二者都
either...or...或者...或者...
neither...nor...既不...也不...
as well as 也、连同
not only...but (also)... 不但...而且...
e.g.
I used to live in Paris and London.
我过去住在伦敦和巴黎。
Both Jane and Jim are interested in pop music.
詹妮和吉姆对流行音乐都很感兴趣。
She is not only kind but also honest.
她不但和蔼而且诚实。
Bob as well as his parents is going on holiday this summer.
鲍勃和他的父母今年夏天要去度假。

2.表示转折关系
常用来表示转折关系的并列连词有如下几个:
but 但是
yet 然而
still 仍然
while 然而
while 然而、偏偏
e.g.
The winter in Beijing is very cold while that of Kunming is warm.
北京的冬天很冷,然而昆明的冬天却很温暖。
I explained twice, still he counldn't understand.
我解释了两遍,然而他却还不懂。

3.表示选择关系
表示选择关系的并列连词:
or 或者
or else 否则
otherwise 否则
neither...nor... 既不...也不...
either...or... 或者...或者...
e.g.
Would you like leave or would you like to stay?
你是想走还是想留?
You can come either on Saturday or on Sunday.
你可以星期六来也可以星期天来。
Neither you nor I nor anyone else believes such things.
不管你我或者其他任何人都不会相信这件事。

4.表示因果推理关系
表示因果关系的并列连词主要有so,for,then,therefore 等。
e.g.
The air here is polluted, so the crops are dying.
这里的空气受到了污染,所以庄稼快死了。
The leaves of the trees are falling, for it's already autumn.
树叶在落下,因为秋天已经到来了。


并列连词注意事项:
并列连词for引导的分句只能放在句尾,前面用逗号隔开,表示补充说明的微弱理由,只是为前面的内容提供判断的理由,有时译为并列的某种形式。
这与because不同,because引导的是一种明确的因果关系,解释原因,常可回答why的提问。
几个特殊并列连词用法:
一、表示并列关系的and,or,well,as,not only...but also... 等连词也有比较活跃的用法。
and 作为并列连词有多重含义,除了可以表示并列关系外,还可以表示顺承、目的、条件、反复等关系。
e.g:He went to market and bought some vegetables.(表示顺承,动作的先后发生)
他到市场买了一些蔬菜。
Come and help me out.(表示目的)
过来帮我一下。
Be careful and you'll make fewer mistakes.(表示条件)
如果仔细,你所犯的错就少。

二、or 与 either...or...
or表示为“否则”的话,前句一般是祈使句,后句用一般将来时。
在表示选择关系时or 与 either...or... 用法相同,但 either...or...更具强调性。
在多个对象进行选择时,可以用A or B or C... , either A or B or C... , neither A or B or C... 。
e.g:Either Jim or Jake or Jeff knows about this.

三、as well as 与not only... but also...
名词+as well as+名词作主语时,强调前面的名词,谓语动词要根据前面的名词而定。
not only...but also...连接名词作主语时,其强调在后者,谓语动词要根据后面的名词而定。
e.g:China as well as many other countries loves peace.
中国与世界上的其他许多国家一样热爱和平。
Not only Bill but also his parents want to go traveling by bike.
不仅比尔而且他的父母都想骑自行车去旅游。
注:当or,neither...nor...,either...or 等连接主语时,谓语动词由or或nor后面的部分而定。
并列连词表示关系:

种类

用法 

举例 

并列连词

表示转折关系

but, yet等

表示因果关系

For, so等

表示并列关系

And, or, either…or,
neither…nor, not only..
but also, as well as等


“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?