The course normally attracts 20 students per year,___up to half will be from overseas.选项：A.in which B.for which C.with which D.of whom
问题描述：
The course normally attracts 20 students per year,___up to half will be from overseas.
选项：A.in which B.for which C.with which D.of whom
答
应该是D吧。后半句应该这样说up to half of them will be from overseas如果将后半句变为定语从句，注意后面的定语从句是修饰students的，所以就应该用who或者whom来引导，把介词of提前后，后面应该用who的宾格形式，所以用whom引导。
答
选D. 可以把句子还原为 up to half of the 20 students will be from overseas.
答
D.of whom
先行词是students
把先行词代入从句,句子是
up to half 【of the students】will be from overseas.
他们中的一半来自海外
所以把【of the students】换成连接词就是 of whom
答
选D
这个课程通常每年吸引20名学生（参加），在他们中间有半数来自海外。
of whom 就是指代在他们中间 of 20 students