This is the 7557th most frequent Polish word.
kupiañsku
The word "kupiańsku" does not exist as a standalone term in Polish; it may be a misspelling or incorrect form.
In this sentence, 'Kupiańsku' is the locative form of the proper noun 'Kupiańsk', indicating the location where the action of spending the vacation takes place.
W Kupiańsku spędzamy wakacje każdego lata.
We spend our vacation in Kupiańsk every summer.
Here, 'Kupiańsku' modifies the noun 'ulice' (streets) to specify the location desribed, using its locative case.
Wiedziałem, że ulice w Kupiańsku są bardzo zatłoczone.
I knew that the streets in Kupiańsk are very crowded.
'Kupiańsku' in this example is used in the locative case to describe the place where parks and architecture exist.