Preposition

[Dinhtuong]

- Could you help me more understand about preposition of place :
why do we use :"... in a car." not "... on a car." as "... on a bus / train / plane".
- When we want to describe the position of a place or thing, we say" on the right/left" or "to the right/left".
- sometimes, I hear "What's going on?" what does question mean? Is is the same question "What are you doing?"

[Tdol]

Often prepositions can seem to be illogical. In your example with the difference between cars/trains, etc, we tend to use 'on' for public transport.

[2006]

"What's going on?", in most cases, is not the same as "What are you doing?'
"what's going on?" usually means 'What's happening?' or 'What happened?'
For example, you arrive home from work to see many people on the street and many police cars in your neighborhood. You ask someone, 'What's going on?'

Your two sentences can sometimes have the meaning. If you see someone doing something that you didn't expect or you don't approve of, you can say "What are you doing?" or "What's going on?"