whose 是所有格，意思是“谁的”，先行词指人或物，在定语从句中充当定语。后面一般跟名词。

whom 是who的宾格，意思是“谁”，先行词指人，在定语从句中充当宾语。

相关介绍

He asked me with whom I had discussed it.

他问我和谁讨论过此事。

Whom do the police suspect?

警方怀疑谁？

Whose is that farm over yonder?

那边的农场是谁的？

I can't remember whose idea it was for us to meet again.

我记不清我们再次会面是谁的主意了。