I looked out of the window and saw Tim on his bike cycling along the road.

问题描述:

I looked out of the window and saw Tim on his bike cycling along the road.
on his bike请教这里为什么用on 有没有具体的例子呢,

在(公共交通工具)上
John got some sleep on the plane.
约翰在飞机上睡了一会儿.