This is the 827th most frequent Croatian word.
njegovoj
"Njegovoj" means "his" in the dative or locative case in English.
The word 'njegovoj' indicates the possessive 'his' and is in the dative case, modifying 'sister'.
On je dao knjigu njegovoj sestri.
He gave the book to his sister.
Here, 'njegovoj' is in the dative case, describing the possessive 'his' in relation to 'presentation'.
Prisustvovali smo njegovoj prezentaciji.
We attended his presentation.
In this sentence, 'njegovoj' functions as a possessive pronoun in the dative case, referring to 'his' mother.