This is the 326th most frequent Hebrew word.
אותן
"Them" (feminine, plural).
In this sentence, 'אותן' is used to refer to the feminine plural noun 'שירים' (songs), acting as a direct object pronoun referring back to the previously mentioned noun.
אני אוהב לשמוע את השירים ולשיר אותן.
I love to listen to the songs and sing them.
Here, 'אותן' refers to the feminine plural noun 'הילדות' (the girls). It's employed as a pronoun in the verb context to replace the noun in the object of the action.
ראיתי את הילדות ושאלתי אותן על הלימודים.
I saw the girls and asked them about their studies.
In this sentence, 'אותן' refers back to the feminine plural noun 'ההזדמנויות' (opportunities), functioning as a direct object pronoun to avoid repetition.