I made an infographic to answer some of my students questions about prepositions and vehicles (buses, cars, trains planes etc.) I thought it would also make a nice blog post where I could give some more examples.
IN a bus is also possible –
“I saw a strange man in the bus last night.”
But ON is the most natural.
“I forgot my umbrella on the bus.”
“I met a famous actor on the plane!”
“I read the newspaper on the train every morning.”
Here are some recent news headlines using the more natural ON.
San Francisco Chronicle
The Daily Telegraph