定语从句中,引导词如果是非谓语动词时,引导词可省略,如果非谓语动与先行词表主动用doing,被动用done,将来用to do 或者将来的被动用to be done,引导词介词宾语时,先行词与介词宾语不能省略。
例如:
The man (who is talking) with my mother is my teacher.=The man( talking) with my mother is my teacher.
This is our school (which was built) ten years ago.=This is our school (built ) ten years ago.
This is the work which wil be finished in an hour.=This is the work to be finished in an hour.
I'm the person who will ask you a question.=I'm the person to ask you a question.
当介词在定语从句的后半部分是,作宾语的关系代词可省,当介词紧跟在先行词后是关系代词不可省;如:
Miss Li is the person( whom) my mother is talking with .句中whom可以省略。
=Miss Li is the person with whom my mother is talking with .句中whom不可以省略。
当引导词在从句中充当介词宾语的时候是可以省略的,其他时候应该不行吧