在定语从句中,关系代词that ,which,whom 在定语从句中作宾语宾语时可以省略,例如
He found the book ( which/that ) he lost yesterday.
This is the boy (whom ) I talked of the other day.
如果定语从句中出现把从句中的介词提前到关系代词which和whom 之前,这时候关系代词which和whom 作介词宾语时,关系代词不能省,介词提前关系词不能用that .
This is the pen ( which /that) he wrote his composition with.在这个句子中which/that可省.
This is the pen with which he wrote his composition.这个句子中 which 就不能省.
I like the boy (whom ) we played football with.
I like the boy with whom we played football .
追答“介词 + 关系代词”引导的定语从句时,介词的宾语只能用which（指物）和whom（指人）,即：介词+which/whom.不能用that 和who.
不是who和which
追问那这个而且不能用who和which是不是错了，应该说成是，不能用who和that,这样理解对吗？谢谢！
还在线吗？帮我一下谢谢！
追答嗯呐
是这样
追问十分感谢,懂了
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