当先行词指人,且定语从句中需要主语时,用who,需要宾语时用whom,口语中who可以代替whom作宾语.
eg：The girl who is talking to the teacher is Mary.
The girl whom/who our teacher is talking to is Mary.
当先行词指人,且定语从句中需要主语时,用who,需要宾语时用whom,口语中who可以代替whom作宾语.
eg：The girl who is talking to the teacher is Mary.
The girl whom/who our teacher is talking to is Mary.