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．
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．
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．
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．
It's six o'clock．It is high time that we went home now．
1. My bike is missing. I can't find ____ anywhere.
A. one B. ones C. it D. that
2. ---- Who's that? ---- ____ Professor Li.
A. That's B. It's C. He's D. This's
3. ____ was Jane that I saw in the library this morning.
A. It B. He C. She D. That
4. ---- Have you ever seen a whale alive?
---- Yes, I've seen ____.
A. that B. it C. such D. one
5. The color of my coat is different from ____ of yours.
A. this B. that C. it D. one
6. ____ will do you good to do some exercise every morning.
A. It B. There C. Those D. You
7. We think ____ our duty to pay taxes to our government.
A. that B. this C. its D. it
8. The climate of Shanghai is better than ____ of Nanjing.
A. that B. it C. which D. what
9. ____ four years since I joined the Army.
A. There was B. There is C. It was D. It is
10. How long ____ to finish the work?
A. you'll take B. you'll take it C. will it take you D. will take you
11. It was through Xiao Li ____ I got to know Xiao Wang.
A. who B. whom C. how D. that
12. It was in the rice fields ____ we had our league meeting.
A. where B. that C. in which D. on which
13. It was on October 1st ____ new China was founded.
A. which B. when C. as D. that
14. Was it because he was ill ____ he asked for leave?
A. and B. that C. that's D. so
15. Mary speaks in a low voice; ____ is difficult to know what she is saying.
A. it B. that C. so D. she
16. It was ____ I met Mr Green in Shanghai.
A. many years that
B. many years before
C. many years ago that
D. many years when
17. ____ is not everybody ____ can draw so well.
A. It, all B. It, that
C. There, who D. There, that
18. So ____ that no fish can live in it.
A. shallow is the lake B. the lake is shallow
C. shallow the lake is D. is the lake shallow
1~5 CBADB 6~10 ADADC 11~15 DBDBA 16~18 CBA