This is the 1094th most frequent Polish word.
najlepszą
The Polish word "najlepszą" means "the best" (feminine singular, accusative form).
In this sentence, 'najlepszą' refers to the superlative adjective form modifying the noun 'książkę' (book) and agreeing in case and gender with it.
Piotr wybrał najlepszą książkę w bibliotece.
Peter chose the best book in the library.
Here, 'najlepszą' is used as a descriptor for 'okazję' (opportunity) and conveys a comparative emphasis that is matched for gender, number, and case.
Anna zawsze szuka najlepszą okazję.
Anna always looks for the best opportunity.
In this example, 'najlepszą' describes 'restaurację' (restaurant), identifying it as the most outstanding among a group in a descriptive context.