Grammar4th主语从句.doc

Grammar 4th
主语从句
名词性从句的功能相当于名词词组。按其句法功能,名词性从句可分为主语从句、宾语从句、表语从句和同位语从句。连接这些从句与主句的关系词主要有三类:
:that (无有词义), whether (是否), if (是否)
:who (谁,主格), whom (谁,宾格), whose (谁的,所有格), what (什么),
which (哪个,哪些)
:when (什么时候), where (什么地方), why (为什么), how (怎样)
I、that引导的主语从句
,但在主语从句中不作任何成分,只起连接作用。that引导的主语从句既可放在句首,也可放在句后。但是为了保持句子的平衡,常用it作形式主语,把真正的主语从句放在句后。例如:
That the attempt to save her had failed soon became widely known.
That he made a mistake is strange.
That he survived the accident is a miracle. (=It is a miracle that he survived the accident.)
It is possible that he hasn’t received the letter.
It is evident that he has finished the task.
,也可放在句后,但是在下列情况下that主语从句不可提前。例如:
1)在It is said that…,It is reported that….It is estimated that…等结构中的主语从句中不可提前。It is reported that a bank was robbed ,
误:That a bank was robbed yesterday is reported.
正:A bank is reported to have been robbed yesterday.
2)在It occurred / happened...结构中的主语从句不可提前。
It happened that he was not in the office that day.
It occurred to me that I had a good idea.
误:That I have a good idea occurred to me.
3)含主语从句的复合句是疑问句时,主语从句不可提前。例如:
Is it true that you will give up the job?
。常见的有4种句型。
It is natural that people should cry.
It’s a great pity that you can’t help us.
常见的4种句型搭配关系如下:
1) It + be + 名词+ that --从句