"Do you have some water?"
Translation:Macie trochę wody?
I was surprised by "wody", was expecting "wodę"....(fem. sg. acc.)...but then I don't know the rules yet....
So from the declension of "woda" at... https://en.wiktionary.org/wiki/woda#Polish
we're either using nom. plural, acc. plural, gen. sing. or voc. plural (unlikely)
which is it please?
Not sure that I agree; a normal rule in English is that "some" is used with affirmative and "any with negative and interrogative - eg, "I've got some water but he hasn't got any"; "have you got any water? We desperately need some". nb, if the interrogative is used to make an offer, then "some" is normal - eg "Do you want some water?" I realise that the suggested answers try to mirror the Hungarian form, but at least for the sake of non-mother tongue English learners, we should depart too far from standard English. Hope this helps.