Is there the difference between jump you and jump at you? I am asking since I see the same translation of them from the context.
She looked at him, scowling with an anxiety she did not like to admit to herself, at the fresh rips in the knees of his blue jeans, the streaks of dirt grained deep in his shirt, a darkening bruise on the cheekbone under his left eye. “Okay, did the big boys jump you in the schoolyard this time, or when you got off the bus?”
A WIND in the DOOR by Madeleine L’Engle
and an another example:
Maybe you were surprised that I didn't jump at you