If in a train or bus some unknown elderly but rude passenger particularly a man, an old man, sitting on a seat which was already reserved by me, how to ask him to get up from there(the seat), Is "Get off my/the seat" is a correct expression when I don't want to be polite to the old man
Please note these usages:
get off a train, boat, plane, bicycle, motorcycle, bus: means of transportation or a surface.
- Hey, Johnny, get off that roof right now!
get out of an x: when one is inside something: Get out of a car, get out of a house.
- Hey, Johnny, get out of here! [leave this place: idiomatic]
For seats, we say get out of my seat as we considering a person to be sitting in a seat.
You would simply say: This is my reserved seat. Get out of it.
Whether old or young, not saying "please" can be seen a slightly curt or abrupt.