This is the 674th most frequent Czech word.
kterému
"To which" or "to whom" (dative case).
Here, 'kterému' is used as a relative pronoun meaning 'to whom', indicating the person receiving the book in the sentence.
To je muž, kterému jsem dal knihu.
This is the man I gave the book to.
In this context, 'kterému' functions as a relative pronoun referring to 'člověka' and links to the action of being awarded.
Znám člověka, kterému bylo uděleno vyznamenání.
I know a person who was awarded a medal.
Here, 'kterému' indicates a possessive relative pronoun meaning 'to whom' or indicating possession regarding the stolen toy.