一、介词规则
by条款：骑车、乘(驾)车、乘船、乘飞机可以使用介词by。
1.by 后跟"光棍"名词，即名词不加任何修饰。如：by bike/bus/car/train/ship/boat/plane。
如：She is going to the Great Wall (长城) by car/ bus.
2. by ship 可用by sea表示;by plane 可以用by air 表示。如：
a. How long does it take by ship/sea?
b. They often come back by plane/air.
in/on条款：步行、骑车、乘车、乘船、乘飞机可以使用介词 in/on。
1.步行只可用on foot。(注意：步行不用by foot)
如：Sometimes I go to school on foot.
2. 骑自行车须用介词 on ：on a/ one's bike。
3. 乘车、乘船、乘飞机可用in也可用on： in/ on a bus/train/ship/boat/plane。
4. 乘坐小汽车应使用 in a car，不用 on a car。
条款说明(一)
1. "by +名词"短语，多可以用in/on 短语替换来表示"骑、乘"之意。如：
a. His father goes to work by bike.
→His father goes to work on a bike.
b. They go to the railway station (火车站) by car.
→They go to the railway station in a car.
2. by sea，by air 是一种比较随便的口语结构，故不宜用in 短语和on短语进行改写。即：