"Whom are you calling?"
Translation:Do kogo dzwonisz?
I think this sentence might even be grammatically correct, but it would not mean "whom are you calling", it would have something to do with church bell ringing.
If we say "dzwonić na policję", why don't we say "NA kogo dzwonisz / dzwonicie?" here?
Mostly it's "do", "na" is only used with a few exceptions, rather... institutions?
There's also "po", when in fact you are calling to ask someone to come to where you are. So "po policję" makes a lot of sense.
That doesn't make any grammatical sense. "do" must precede the person that you are calling (and in this case, 'whom').
While Polish is pretty flexible with its word order (despite the fact that some orders only work in specific situation, like poetry and songs), there are still some rules that put some limitations.
One of them is that a preposition should come directly before the word it is referring to. „Do kogo dzwonisz?” is the normal order, „Dzwonisz do kogo?” is also grammatically correct and might be used to express surprise at who the person that is being called is. All the other word orders are wrong, because „do” would no longer stand in front of „kogo”.