—Do you know the boy is sitting next to Peter?—Yes.He is Peter's friend.A. whomB. whoC. w

问题补充：

—Do you know the boy is sitting next to Peter?

—Yes.He is Peters friend.

A. whom

B. who

C. which

D. /

答案：

A. whom

(答案→)B. who

C. which

D. /

解析：考察定语从句。当先行词是指人的名词时，从句中的关系代词可以死who,做主语。不能省略。Which指代的先行词必须是物。句意：—你认识那个坐在彼得旁边的男孩吗？—是的。他是彼得的朋友。