Dave's ESL Cafe's Student Discussion Forums

[Teo]

I'm sitting __ a bus.
Which preposition should I use to fill in the above blank, on or in?
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Thank you very much for your reply.

[battlecryorsilence]

"On" is a better choice of preposition than "in" for your sentence: "I am sitting on a bus." There is a very general and informal rule regarding prepositions and vehicles: the preposition "in" tends to be used for small, enclosed vehicles, and the preposition "on" tends to be used for large, enclosed vehicles. For vehicles with no enclosure at all (for instance, a bicycle), "on" is almost always correct.

Here are some examples:

I am sitting in my car.
I am sitting in the truck.
My friend and I are sitting in the paddleboat. (paddle boat = a very small kind of boat)

I am sitting on the bus.
I am sitting on the plane.
I am sitting on the train.
She is already on the boat (a big boat; a cruise ship, for instance).

I am sitting on my bicycle.

One way to check for the appropriate preposition is to ask yourself whether you would get "out" of the vehicle or "off" of the vehicle. We get in and out of cars and trucks, we get on and off of planes, trains, and busses, and we sometimes fall off of bicycles! "In" goes with "out", and "on" goes with "off."
I hope this answer is helpful to you.