解释:1)whom指代人本身,相当于先行词Mr Wu,在定语从句中充当宾语。2)whose相当于先行词的所有格形式:Mr Wu's,在定语从句中充当某个名词daughter的定语。3)该题的先行词是Mr Wu,代入从句中为:whose daughter is a French interpreter.= Mr Wu's daughter is a French interpreter.如果是whom,则Mr Wu必须在从句中做宾语,可是该句daughter is a French interpreter并不缺少什么宾语,它是一个主系表句型,不缺宾语。