This is the 2857th most frequent Polish word.
książek
The Polish word "książek" means "books" (genitive plural form of "książka").
"Książek" is used here as the plural genitive case of "książka" (book), indicating possession.
Mam dużo książek na półce.
I have many books on the shelf.
"Książek" is in the plural genitive case, used after a negative verb.
Nie przyniosłam żadnych książek do szkoły.
I didn't bring any books to school.
"Książek" is in the plural genitive case as it describes the quantity of items in the phrase "pełna książek" (full of books).