通过例句理解.
The means of transportation that I chose at ordinary times is the rail transportation basically
我平时选择的交通工具基本上是轨道交通------特指某种交通工具
riding a horse asa means of transportation.
骑马来当作交通工具------泛指
Bike is a convenient means of transportation.
自行车是很方便的运输物品.-----运输方式