定语从句引导词省略有以下几种情况。
1、在非正式文体中,用于指人的关系代词who whom, that 指代先行词在定语从句中作宾语时通常可以省略;用于指物的关系代词which和that指代先行词在定语从句中作宾语时中也通常省略。例如:
1)The man (whom/who/that) we have just seen is a famous writer.
2)Where is the book (which/that) I bought last week?
2、 关系代词指代先行词在定语从句中作表语时,只用that ,它既可以指人,也可以指物,但时常省略。例如:
1)He is no longer the man that he used to be.
2)This is no longer the dirty place (that) it used to be.
3、以the way为先行词的限制性定语从句,如果先行词way在定语从句中做状语,通常以in which或 that 引导,但在非正式文体中,人们通常省略in which或 that 。例如;
1)The way (in which) he spoke to us was suspicious.
2)I don’t like the way (that) you laugh at her.
4、以place为先行词的限制性定语从句,如果先行词place在定语从句中做状语,通常以where 引导,但在非正式文体中,人们通常省略where。例如:
1)This is the place (where) we met yesterday.
5、以reason为先行词的限制性定语从句,如果先行词reason在定语从句中做状语,通常以why引导,但在非正式文体中,人们通常省略why。例如:
1)That is the real reason(why) he did it.
6、以time,day,week,month,year等为先行词的限制性定语从句,如果先行词在定语从句中做状语,通常以when引导,但在在某些句型和某些时间状语中,人们通常省略when。例如:
1)But help never stopped coming from the day she fell ill.
2)Each time he came, he did his best to help us.
注:针对以上情况,下列情形定语从句的引导词不能省。
1、如果作介词宾语且介词提前,这时关系代词指人用whom,指物用which,而且均不能省。例如:
1)Gun control is a subject about which Americans have argued for a long time.
2) She brought with her three friends,none of whom I had ever met before.
2)在非限制性定语从句中,无论是关系代词还是关系副词均不能省。例如:
1) They have won their last three matches, which I find a bit surprising actually
以上内容转自
http://fangxinzg.blog.sohu.com/182339964.html规则条目有很多,如果不是为了考试,日常使用的话,只需记得限制性定从,引导词做主语不能省,做宾语一般可以省略,就可以了。(非限制性定从是无论如何不能省的)