We can use the following prepositions to express movement on a transportation:

• by

• on

• in

By - General Ways to Travel

• When talking about general ways to travel, we always use the preposition “by.” We can travel by bike, by motorcycle, by car, by van, by lorry, by truck, by train, by plane, by bus, by ship, by tram, or by boat.

• We can also use by to refer to the transportation environment (by sea, by land, by air) or the surface area (by rail, by road, by water).

On

• If you can stand or walk on the vehicle, then we use on. So we go on a ship but in a rowboat; we go on a bus but in a taxi.

• Other examples of when we use on would be on a plane, on a tram, on a ferry, on a subway, or on a train — again, you can stand or walk on all of these, even when they are in motion.

• Finally, if we actually sit or stand upon the top of the vehicle, then we also are on it. So we go on a bicycle, on a surfboard, on a motorcycle, on a skateboard, on skis, on ice skates, on a snowboard, etc. (the vehicle is physically underneath)

In - Specific Transport Vehicles

• When we talk about specific transport vehicles, however, we need to switch to either in or on. How do we know which to use?

• Easy, if you remember this simple rule: If you must sit inside the vehicle, we use in.

  
  

• Some examples would be: "in a car", "in a truck", or "in a helicopter": it is almost impossible to stand in them.

Walking: ON and BY

• And, where does that leave the most basic form of transportation — walking? Well, the same rules apply: we go by foot (meaning as a general way of moving from one place to another) or we go on foot (meaning we are on top of our feet!). Therefore, both are correct ways to describe walking.

Look out for the small difference

• We traveled to France by train. (train is the way of travel; a general description of how we traveled). There is no article the, a

• We were on a train to France.

• We went to France on a nighttime train.