You are sitting on a bus moving through the city streets. With respect to which bodies you are: a) in motion b) at rest.

Sitting in the passenger compartment of the bus, the passenger is at rest in relation to all objects in the bus itself and in relation to the bus itself (if the passenger sits in place, and does not move around the cabin). With regard to everything outside the bus – buildings, streets, people on the street, etc. – the passenger is on the move.