it句型大掃描
研究近年的高考試卷中可以發(fā)現含it的句型年年考到?？梢?jiàn)it句型的重要性和使用的普遍性?，F根據其用法特點(diǎn)可歸納為２０個(gè)句型．
1. It is +被強調部分+ that ...
該句型是強調句型。將被強調的部分放在前面，其它部分置于that之后。被強調部分可以是主語(yǔ)，賓語(yǔ)，表語(yǔ)或狀語(yǔ)。強調的主語(yǔ)如果是人，that可以由who換用。如果把這種句型結構劃掉后，應該是一個(gè)完整無(wú)缺的句子。這也是判斷強調句型與其它從句的方法。
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 +被強調部分+ that ...
該句型也是強調句型。主要用于強凋時(shí)間狀語(yǔ)，譯成漢語(yǔ)＂直到．．．才．．．＂，可以說(shuō)是not ... until ...的強調形式。
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 .....
該句型中it是形式主語(yǔ)，真正的主語(yǔ)是that引導的主語(yǔ)從句，常譯為＂清楚（顯然，真的，肯定．．．）＂ 是主語(yǔ)從句最常見(jiàn)的一種結構。
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 ...
該句型和上一個(gè)同屬一個(gè)句型。由于主句中的形容詞不同，that后的從句中要用虛擬語(yǔ)氣（should +動(dòng)詞原形），should可以省去。建議記住該句型中的形容詞。
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 ...
該句型中的it仍是形式主語(yǔ)，真正主語(yǔ)是that引導的主語(yǔ)從句。該結構常譯為＂據說(shuō)（據報道，據悉．．．）＂。
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 ...
該句型和上一個(gè)同屬一個(gè)句型。主句中的過(guò)去分詞是表示請求，建議，命令等詞時(shí)，that 后的從句要用虛擬語(yǔ)氣（should +動(dòng)詞原形），should可以省。常譯為＂據建議；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 ...
該句型中，that后的從句一般用虛擬語(yǔ)氣（should +動(dòng)詞原形），should可省去．表示出乎意料，常譯為＂竟然＂。沒(méi)有這種意義時(shí)，則不用虛擬語(yǔ)氣。
It is a pity that such a thing ( should ) happen in your class.這種事竟然發(fā)生在你們班上，真是遺憾！
It is a pity that he is ill.他生病了，真遺憾！
8. It is time ( about time ,high time ) that ...
該句型中that后的從句應該用虛擬語(yǔ)氣，值得注意的是①常用過(guò)去時(shí)態(tài)表示虛擬．②有時(shí)也用should +動(dòng)詞原形，should不能省。常譯為＂是（正是）．．．的時(shí)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 ...
該句型要和上一個(gè)句型區別開(kāi)來(lái)。該句型中的that從句不用虛擬語(yǔ)氣，而用完成時(shí)態(tài)。至于用什么完成時(shí)態(tài)，由主句的謂語(yǔ)動(dòng)詞的時(shí)態(tài)決定。如果是一般現在時(shí)，后面從句用現在完成時(shí)態(tài)；如果是一般過(guò)去時(shí)，后面從句則用過(guò)去完成時(shí)態(tài)。該結構中that可以省去；it有時(shí)用this替換．常譯為＂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 ...
該句型主要用作處理瞬間動(dòng)詞的完成時(shí)，又要和表示一段時(shí)間的時(shí)間狀語(yǔ)連用的問(wèn)題。主句中是時(shí)間作表語(yǔ)，其時(shí)態(tài)是現在時(shí)或完成時(shí)，since引導的從句通常是一般過(guò)去時(shí)態(tài)，而且是瞬間動(dòng)詞。如果主句是一般過(guò)去時(shí)，從句則用過(guò)去完成時(shí)。
It is ( has been ) 5 years since his father died.
11. It is ... when ...
該句型中的when引導的是一個(gè)時(shí)間狀語(yǔ)從句，主句中的it指時(shí)間，表語(yǔ)由具體的時(shí)間充當。常譯為＂當．．．的時(shí)候，是．．．＂。
It was 5 o’clock when he came here.
12. It be ... before ...
該句型主句中的it指時(shí)間,主句中的時(shí)態(tài)常是將來(lái)一般時(shí)或過(guò)去時(shí)兩種時(shí)態(tài)．主句中的表語(yǔ)多是long, not long , 3 days , 2 weeks等表示時(shí)間段的詞或短語(yǔ)。常譯為＂．．．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...
該句型中it是形式主語(yǔ)，that引導的是主語(yǔ)從句，主句中的happen , seem等詞是不及物動(dòng)詞．
It happened ( so happened ) that he met his teacher in the street.碰巧．．
It seems that he will be back in a few days.看來(lái)．．．
14. It takes sb. ... to do sth.
該句型中的不定式是真正的主語(yǔ)，it是形式主語(yǔ)，句型中的直接賓語(yǔ)是時(shí)間。常譯為＂做．．．要花費某人．．．＂。
It took thousands of people many years to build the Great Wall.
15. It is no good (use ) doing sth.
該句型中的真正主語(yǔ)是動(dòng)名詞短語(yǔ)，主句中的表語(yǔ)可以是no good , ( not any good ) , no use , ( not any use )。
It is no good learning English without speaking English.
16. It doesn’t matter whether ( if ) ...
該句型中whether(if)引導的從句是真正主語(yǔ)，該句型常譯為?。⒉徽摚ㄊ欠瘢疀](méi)關(guān)系．．．。
It doesn’t matter if they are old.
17. It is kind ( of sb. ) to do sth.
該句型中的不定式短語(yǔ)是真正主語(yǔ)，如果不定式的邏輯主語(yǔ)是由of引起，主句中的形容詞必須是能表示邏輯主語(yǔ)特征的形容詞。常見(jiàn)的有：bad , brave , careless, clever , cruel , foolish , good（好心的）, honest , horrible , kind , lazy , modest , naughty , nice（有教養的）, polite, rude , silly , stupid , wise , wrong（錯誤的）等。這個(gè)句型可以改寫(xiě)為：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.
該句型與上一個(gè)同屬一個(gè)句型。如果不定式的邏輯主語(yǔ)是由for引起，主句中的形容詞通常是表示重要性，緊迫性，頻繁程度，難易，安全等情況的形容詞。常見(jiàn)的形容詞有：①important, necessary, natural②easy , safe , common , normal , hard , difficult , dangerous , unusual, rare , impossible , pleasant等?！ ≡冖僦械男稳菰~作表語(yǔ)可以用從句改寫(xiě)，如：
It is important for her to come to the party.
= It is important that she (should ) come to the party
19. It looks ( seems ) as if ...
該句型中it無(wú)意義。as if引導一個(gè)狀語(yǔ)從句。常譯為，＂看起來(lái)好象．．．＂如果與事實(shí)不相符合，則用虛擬語(yǔ)氣．
It looks as if he is ill.（真的病了）
It looks as if he were ill.（沒(méi)有生?。?div style="height:15px;">
It seemed as if he were dying.
20. We think it important to learn a foreign language.
該句型中的it作形式賓語(yǔ)。為了記憶方便我們可稱(chēng)該句型為"6123結構"?！ ?指主句中常用的動(dòng)詞：think, believe, make, find, consider, feel； 1指的是形式賓語(yǔ)it； 2指的是賓補的兩種形式：形容詞或名詞； 3指的是真正賓語(yǔ)的三種形式：不定式短語(yǔ)，動(dòng)名詞短語(yǔ)或that引導的賓語(yǔ)從句。
We think it our duty to clean our classroom every day.
He felt it important learning English well.
