This is the 1549th most frequent Polish word.
córki
"Daughters."
Here, 'córki' is the plural, accusative form of 'córka,' used as the direct object of the sentence to indicate possession.
Mam dwie córki.
I have two daughters.
Here, 'córki' is the singular, genitive form of 'córka,' used to indicate direction towards someone's daughter.
Idziemy do córki.
We are going to the daughter.
Here, 'córek' is the plural, genitive form of 'córka,' used to indicate possession in context of relationship.