______are they talking with about the matter?

问题描述:

______are they talking with about the matter?
A whom B who 选哪个?改成陈述句应该是 they are talking with sb about the matter .所以充当宾语应该用whom啊,可是答案是who ,为什么?

注意,这不是定语从句,而是特殊疑问句.whom无法引导特殊疑问句.