There are flowers and trees on ___ side of this road.咋填?

问题描述:

There are flowers and trees on ___ side of this road.咋填?
a.all b.every c.both d.either
请说明原因

选D,表示马路的任何一边,用于两者之一.
B是用于三个或三个以上的东西之一.
A和C用于复数.