語法精講The Use of “It” (1) as Subject“It”的用法(1)作主語

　　1.it用作人稱代詞，指前面提到過的人或物。

　　The frog is not a warmblooded animal.It is a coldblooded one.

　　青蛙不是溫血動物，而是冷血動物。(指代the frog)

　　—Who is knocking at the door?

　　誰在敲門？

　　—It is me.

　　是我。(指代人)

　　—What is this?

　　那是什么？

　　—It is a flag.It is hers.

　　是一面旗，那是她的。(指代this或that)

　　2.it也可用作非人稱代詞，表示天氣、日期、時間、溫度、距離、環境情況等。

　　It was very noisy at the moment.

　　現在外面很吵。(指環境情況)

　　—What time is it?

　　幾點了？

　　—It is eight o’clock.

　　8點了(指時間)

　　It is five kilometers from the office to my home.

　　從辦公室到我家5千米。(指距離)

　　3.it常用作形式主語或形式賓語，而把真正的主語或賓語(不定式、動詞ing形式或名詞性從句)置于句尾，以滿足句子的需要。

　　it作形式主語，常用于下列結構：

　　1)It is+cruel(kind,brave,nice,rude,wise,stupid,clever;foolish,polite...)of sb. to do sth.

　　2)It is important(necessary,possible,impossible,easy,difficult,hard...)for sb. to do sth.如：

　　It is foolish of you to waste money.(=You are foolish to waste money.)

　　你浪費錢是愚蠢的。

　　It is necessary for us to study hard.(=To study hard is necessary for us.)

　　對我們來講努力學習是必要的。

　　在這兩個結構中，使用介詞for還是介詞of由前面的形容詞而定；若形容詞修飾人，使用介詞of;若形容詞修飾事，則使用介詞for。

　　3)It is no use(useless,no good)doing sth.

　　It is no use talking with him.

　　跟他談話是沒有用的。

　　此結構中真正的主語通常為動名詞。

　　4)It is said(known,reported,thought,hoped,believed,announced...)that...

　　It is said that he comes from America.

　　據說他來自美國。

　　此結構中真正的主語是名詞性從句，且能變為簡單句，上句可變為：He is said to come from America.即：從句的主語用作主語，謂語動詞仍是主句的謂語動詞，但應存在人稱和數的變化，從句的謂語動詞用不定式表示。如：

　　It was known that he had gone abroad.

　　=He was known to have gone abroad.

　　眾所周知他出國了。

　　【考例1】2006全國高考Ⅰ,26If I can help _________,I don’t like working late into the night.

　　A.so

　　B.that

　　C.it

　　D.them

　　解析:此處考查it的用法。it可用于某些動詞或前置詞的后面，詞義含糊，構成習語。如：You’ll catch it!你可小心點兒!此處If I can help it意為“如果我有辦法的話”。有時我們也可以說It can’t be helped.或There is no help for it.表示“實在沒法兒”。

　　答案:C

　　【考例2】(2006浙江高考，4)_______ is our belief that improvements in health care will lead to a stronger,more prosperous economy.

　　A.As

　　B.That

　　C.This

　　D.It

　　解析:本句考查從句的用法。根據句子結構，that引導的從句為主語從句，作真正主語，因此前邊應有形式主語，而形式主語只能用it,不能用this或that。

　　答案:D

　　【考例3】(2006山東高考，24)I’d appreciate _______ if you would like to teach me how to use the computer.

　　A.that

　　B.it

　　C.this

　　D.you

　　解析:it作appreciate的形式賓語，真正的賓語是if you would like to teach me how to use the computer。it常在hate,like,appreciate等動詞后作形式賓語，指代it之后的內容，對此用法應熟練掌握。

　　答案:B

　　【考例4】(2006全國高考Ⅱ,11) It is no _______ arguing with Bill because he will never change his mind.

　　A.use

　　B.help

　　C.time

　　D.way

　　解析:It is no use+doing...表示“做某事沒有用”。it作形式主語，doing sth.作真正的主語。

　　答案:A

　　【考例5】(2006山東高考，33)Police are now searching for a woman who is reported to _______ since the flood hit the area last Friday.

　　A.have been missing

　　B.have got lost

　　C.be missing

　　D.get lost

　　解析:由句意可知“失蹤”這一動作仍在持續中，故須用進行時態，又由since提示該句時態須用完成時態。

　　答案:A

　　語法精講The Use of “It” (1) as Subject“It”的用法(1)作主語

　　1.it用作人稱代詞，指前面提到過的人或物。

　　The frog is not a warmblooded animal.It is a coldblooded one.

　　青蛙不是溫血動物，而是冷血動物。(指代the frog)

　　—Who is knocking at the door?

　　誰在敲門？

　　—It is me.

　　是我。(指代人)

　　—What is this?

　　那是什么？

　　—It is a flag.It is hers.

　　是一面旗，那是她的。(指代this或that)

　　2.it也可用作非人稱代詞，表示天氣、日期、時間、溫度、距離、環境情況等。

　　It was very noisy at the moment.

　　現在外面很吵。(指環境情況)

　　—What time is it?

　　幾點了？

　　—It is eight o’clock.

　　8點了(指時間)

　　It is five kilometers from the office to my home.

　　從辦公室到我家5千米。(指距離)

　　3.it常用作形式主語或形式賓語，而把真正的主語或賓語(不定式、動詞ing形式或名詞性從句)置于句尾，以滿足句子的需要。

　　it作形式主語，常用于下列結構：

　　1)It is+cruel(kind,brave,nice,rude,wise,stupid,clever;foolish,polite...)of sb. to do sth.

　　2)It is important(necessary,possible,impossible,easy,difficult,hard...)for sb. to do sth.如：

　　It is foolish of you to waste money.(=You are foolish to waste money.)

　　你浪費錢是愚蠢的。

　　It is necessary for us to study hard.(=To study hard is necessary for us.)

　　對我們來講努力學習是必要的。

　　在這兩個結構中，使用介詞for還是介詞of由前面的形容詞而定；若形容詞修飾人，使用介詞of;若形容詞修飾事，則使用介詞for。

　　3)It is no use(useless,no good)doing sth.

　　It is no use talking with him.

　　跟他談話是沒有用的。

　　此結構中真正的主語通常為動名詞。

　　4)It is said(known,reported,thought,hoped,believed,announced...)that...

　　It is said that he comes from America.

　　據說他來自美國。

　　此結構中真正的主語是名詞性從句，且能變為簡單句，上句可變為：He is said to come from America.即：從句的主語用作主語，謂語動詞仍是主句的謂語動詞，但應存在人稱和數的變化，從句的謂語動詞用不定式表示。如：

　　It was known that he had gone abroad.

　　=He was known to have gone abroad.

　　眾所周知他出國了。

　　【考例1】2006全國高考Ⅰ,26If I can help _________,I don’t like working late into the night.

　　A.so

　　B.that

　　C.it

　　D.them

　　解析:此處考查it的用法。it可用于某些動詞或前置詞的后面，詞義含糊，構成習語。如：You’ll catch it!你可小心點兒!此處If I can help it意為“如果我有辦法的話”。有時我們也可以說It can’t be helped.或There is no help for it.表示“實在沒法兒”。

　　答案:C

　　【考例2】(2006浙江高考，4)_______ is our belief that improvements in health care will lead to a stronger,more prosperous economy.

　　A.As

　　B.That

　　C.This

　　D.It

　　解析:本句考查從句的用法。根據句子結構，that引導的從句為主語從句，作真正主語，因此前邊應有形式主語，而形式主語只能用it,不能用this或that。

　　答案:D

　　【考例3】(2006山東高考，24)I’d appreciate _______ if you would like to teach me how to use the computer.

　　A.that

　　B.it

　　C.this

　　D.you

　　解析:it作appreciate的形式賓語，真正的賓語是if you would like to teach me how to use the computer。it常在hate,like,appreciate等動詞后作形式賓語，指代it之后的內容，對此用法應熟練掌握。

　　答案:B

　　【考例4】(2006全國高考Ⅱ,11) It is no _______ arguing with Bill because he will never change his mind.

　　A.use

　　B.help

　　C.time

　　D.way

　　解析:It is no use+doing...表示“做某事沒有用”。it作形式主語，doing sth.作真正的主語。

　　答案:A

　　【考例5】(2006山東高考，33)Police are now searching for a woman who is reported to _______ since the flood hit the area last Friday.

　　A.have been missing

　　B.have got lost

　　C.be missing

　　D.get lost

　　解析:由句意可知“失蹤”這一動作仍在持續中，故須用進行時態，又由since提示該句時態須用完成時態。

　　答案:A