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．

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．

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．

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．

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．

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．

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．

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．

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．

25. I was really anxious about you . You ____home without a word.

A. mustn't leave                     B. shouldn't have left

C. couldn't have left                D. needn't leave

 1-5 BDABD   6-10 BDCDC   11-15 CBABD   16-20 CDADA    21-25 CAACB

十. It 句型归纳