引导词连接什么从句

引导词连接whether，how，what ，why，if，when等具有引导紧贴后面从句功能的词；

定语从句的引导词有关系代词who， whom，which，that， as；关系副词when， where，why；关系形容词whose。

定语从句中引导词的选用主要看先行词在定语从句中作什么成分或者是定语从句中缺什么成分。

1．定语从句中缺主语，修饰人时用who /that，修饰物时用which /that引导。如

Is this the factory which /that makes TV sets？

The man who /that visited our school is from Australia．

2．从句中缺宾语，修饰人时用 who /whom /that或省略引导词；修饰物时用which /that或省略引导词。如

Gone are the days which /that we spent together in the village．

He is the man who /whom /that I think to be worthy of our praise．

3．从句中缺时间状语，用when或介词+which引导。如

The day finally came when /on which I was given a job．

We\'ll put off the outing until next week，when we won\'t be so busy．

4．从句中缺地点状语，用where或介词+which引导。如

Please put the letter on the desk where /on which he can easily find it．

5．从句中缺原因状语或先行词是 reason时，引导词用why /for which / that。如

This is the reason why /for which / that he didn\'t come to the meeting．

6．从句中缺定语，人和物都用 whose引导。如

A child whose parents are dead is called an orphan．

Please pass me the dictionary whose cover is black．

7．当先行词是way时，其定语从句的引导词用in which /that。如

The way in which /that he looks at problems is wrong．

as

引导词as可引导限制性定语从句，也可引导非限制性定语从句。

1．在固定词组the same．．．as，such．．．as中，as引导限制性定语从句。如

He is not such a fool as he looks．

I\'ve bought the same dress as she is wearing．

2．当先行词是整个主句时，可用 as /which引导非限制性定语从句。引导词as和which的区别在于

①as引导的非限制性定语从句可放于主句前、主句中、主句后，而which引导的非限制性定语从句一般放于主句后或句中。

②as常与从句中的know，see， hear，expect等动词连用，也常用于as often happens，as is often the case（常有的事）等句子中；而which一般不用于以上情况。

③as有“正如”的含义，which没有此含义。如

As is well known，Shanghai is a big city．

Some of the roads were flooded， which made our journey more difficult．