no

"No" is the standard Polish equivalent of the English "no" or "not." It functions as a direct negation, serving to contradict a statement, deny a request, or express a negative response to a yes-no question. While it is the universal word for negation, it is often paired with "nie" in colloquial speech. Interestingly, in very casual or regional Polish, "no" can sometimes be used as an affirmative particle (similar to "yeah" or "yep"), though this is a distinct usage that depends heavily on intonation and context.
In conversation
Declining an offer
Chcesz jeszcze trochę kawy?
Do you want some more coffee?
Nie, dziękuję.
No, thank you.
Using 'nie' is the standard, polite way to decline.
Confirming a negative fact
Czy on dzisiaj przyjdzie?
Is he coming today?
Nie, nie przyjdzie.
No, he won't come.
Polish often uses a double negative structure for emphasis.
Examples
Nie, to nie jest prawda.
No, that is not true.
Nie mam dzisiaj czasu na spotkanie.
I don't have time for a meeting today.
Nie widziałem go od tamtego czasu, nie wiem, co robi.
I haven't seen him since then; I don't know what he's doing.