"We are going behind the bus, on which there is not even one person."
Translation:A mögött a busz mögött megyünk, amelyiken nincs egy ember sem.
But we usually say "buszon", not "buszban", although neither is incorrect. So, "amelyiken" is more common.
So, both Hungarian versions translate to the same English sentence, right?
"Mögött" - We are already behind the bus, and we are moving with the traffic.
"Mögé" - We are pulling in behind the bus, to be behind it.
Yes, "We are going behind the bus" could mean either of those.
A bit more likely to be mögé since "going" mostly tends to be used when expressing destination rather than simple movement.
With a different verb, e.g. "We are driving behind the bus", it could be either -- "we are driving, and while we are driving, we are behind the bus", or "we are driving towards the location which is behind the bus, so that we can be behind the bus at the end of the manoeuvre".