This is the 3921st most frequent Chinese word.
个个
"Each; every one."
In this sentence, '个个' is used as a pronoun for 'everyone', emphasizing the inclusiveness of 'every individual person'.
个个都喜欢听音乐。
Everyone likes listening to music.
Here, '个个' emphasizes that all members of a group possess a certain quality, used as an all-encompassing pronoun.
个个是班里的优秀学生。
Everyone is an excellent student in the class.
'个个' is used to describe the entirety of the group where every individual is characterized by the mentioned trait or action.