语法复习6 强调句，it的用法.ppt

语法复****六:强调句、It的用法
一、强调句
(一)强调句句型
1、陈述句的强调句型:
It is/ was + 被强调部分(通常是主语、宾语或状语)
+ that/ who(当强调主语且主语指人)+ 其它部分。
It was yesterday that he met Li Ping.
2、一般疑问句的强调句型:把is/ was提到it前面。
Was it yesterday that he met Li Ping?
3、特殊疑问句的强调句型:
被强调部分(通常是疑问代词或疑问副词)+ is/ was + it
+ that/ who + 其它部分?
When and where was it that you were born?
针对 I met Li Ming at the railway station yesterday. 进行强调。

强调主语:
It was I that (who) met Li Ming at the railway station yesterday.
强调宾语:
It was Li Ming that I met at the railway station yesterday.
强调地点状语:
It was at the railway station that I met Li Ming yesterday.
强调时间状语:
It was yesterday that I met Li Ming at the railway station.

把最后一句改为一般疑问句,并对被强调部分提问:
Was it yesterday that you met Li Ming at the railway station ?
When was it that you met Liming at the railway station ?
(二)not … until …句型的强调句
句型为:It is/ was not until + 被强调部分+ that + 其它部分
普通句:He didn’t go to bed until/ till his wife came back.
强调句:It was not until his wife came back
that he went to bed.
(三)谓语动词的强调
It is/ was … that …结构不能强调谓语,如果需要强调
谓语时,用助动词do/ does或did。
Do sit down. 务必请坐。
He did write to you last week.
上周他确实给你写了信。
Do be careful when you cross the street.
过马路时,务必(千万)要小心啊!
二、 It的用法
(一)作人称代词
it 代替前面(或后面)的单数名词或分句等所表示的事物。
You cannot eat your cake but have it.
(it 代替前面的 cake)
Although we cannot see it, there is air all around us.
(it 代替后面的 air)
They say he has left town, but I don’t believe it.
(it 代替前面 They…town 分句中的情况)
2、代替有生命但不能或不必分阴阳性的东西(包括婴儿)。
Yesterday we saw a big tree. It was fully twenty metres high.
(it 代替前面的 tree)
The baby cried because it was hungry.
(it 代替前面的 baby)
在某些****惯说法中,可以代替人。
---- Someone is knocking at the door, Peter.
---- Who is it?
---- It’s me.
---- Who are singing?
---- It is the children.
---- The light is still on in the lab. It must be the third-year
students doing the experiment.