it做形式主語用法大全學習資料

1、i t 做 形 式 主 語 用 法 大全It 作形式主語常見句型動詞不定式，動名詞或主語從句作主語時，通常把它們放在謂語動詞前， 而用 it 作形式主語，放到句首，常見句型有：1. It + be + 形容詞 +主語從句，如：It is uncertain whether he can come to Jenn'ys birthday party or not.2. It + be + 名詞詞組 + 主語從句，這類名詞有： a fact, a pity, a shame, an honour ， a question 等，如：It 's a pity that you miss

2、ed the exciting football match.It remains a question whether he will come or not.3. It + be + 過去分詞 + 主語從句，這類過去分詞有： announced, believed, expected, hoped, decided, reported, said, shown 等， 如：It is reported that 16 people were killed in the earthquake.It is not decided who will give the operation to th

3、e patient.4. It +不及物動詞(seem, appear, happen等)+主語從句,這類不及物動詞 有：appear, happen, seem等， 如:It seemed that he didn't tell the truth.It happened that I was out when he called.5. It + be + 形容詞 + for sb.)+ 動詞不定式這類句型常用形容詞 easy, difficult, hard, important, possible , wise 等作表語，有時候為了強調(diào)不定式動作的執(zhí)行者，常在不定式前加 for

4、sb ，如：It's necessary for the young to master two foreign language.It is unwise to give the children whatever they want.這類形容詞有： easy, difficult, hard, important, possible ， wise6. It + be + 形容詞 + of sb. + 動詞不定式，這類形容詞常是表示心理品質(zhì) ,性 格特征的形容詞，如： kind, nice stupid, clever, foolish, polite, impolite, sill

5、y, selfish, considerate 等。某人和這些形容詞可以構(gòu)成主系表結(jié)構(gòu)。如：It's very kind of you to help me with the work.=You are kind to help me.It seemed selfish of him not to share his dictionary with others.=He seemed selfish not to share his dictionary with others.7. It + be +名詞詞組+動詞不定式，如：It is not a good habit to sta

6、y up too late.8. It + be +名詞或形容詞+動名詞，這類名詞和形容詞常常是：good, nogood, no use, a waste of, useless, senseles等，如:It' a waste of time talk ing to her any more.It is no use arguing about the matter with him.9. It + take ( sb. )+時間(金錢)+動詞不定式，如：It took the workers almost three years to finish building the da

7、m.It will take a whole day to get to the top of the mountain on foot.實戰(zhàn)演練：1. It is gen erally con sidered un wise to give a child e or she wan ts. (NMET1997)A. however B. whatever C. whichever D. whe never2. I n fact is a hard job for the police to keep order in an importa nt footballmatch. (2001 上海

8、)A. this B. that C. there D. it3. is a fact that En glish is being accepted as an intern ati on al la nguage.(NMET1995)A. There B. This C. That D. It4. Isn ecessary to take off our shoes whe n we en ter the lab? (MET88)A. every oneB. this C. her D. it5. will take you a lot of time to find him in the

9、 crowd.A. It B. IC. WeD. They6. It is no use histhere, the situati on is hopeless now.A. to go B. to be going C. going D. hav ing gone7. It is n ever too late to lear n,?A. is it B. isn 'titC. does it D. doesn 'tit8. is known to all that Shen zhou VI Laun ched Successfully.A. As B. What C. I

10、t D. That9. is reported in the newspaper, the Earthquake in east China's JiangxiProvince killed 13 peopleA. It B. AsC. ThatD. What10. certain that his invention will make people 's life convenient.A. That 's B. This is C. It's D. What's11. that there is another football match on the air this evening.A. It says B. It was said C. It is said D. What was said12. that their daughter got an