is this on the trams as in on top of the trams, on the trams as in inside the trams, or both?
If it were on the tram (not plural), would it start A villamoson, rather than a villamosokon?
Is "villamosokon" really something a Hungarian would say?
I'd expect villamosban, unless we talk about those tables being on the roof of the tram???
Villamosokon is totally fine. When I travel on the tram, a villamoson utazom.
Maybe villamosban in ok too, but it does not sound as natural as -on.
Is this statement general? I'm still not sure in which case we should use "a" and in which not... would the sentence without "a" in the front be wrong?