一个关于英语定语从句的选择题

问题描述:

一个关于英语定语从句的选择题
The settlement is home to nearly 1,000 people ,many of ____left their village homes for a better life in the city.
A.whom
B.which
C.them
Dthose
为什么要用whom,为什么不用who?做的是主语还是宾语啊!还有什么时候用who

whom 作关系代词,指人,引导定语从句,宾格形式,放于介词of后,先行词为people.Who用于主格形式,也可作宾语,但不能放在介词后.