Correção de frases "it's been very quiet..."

Eu tenho um exercício aqui que tenho que dizer se as frases então certas ou erradas e tenho que corrigi-las:

-"It's been very quiet in the house since the children have gone to college"
Está errada, seria "went to college"?

-"I listened to some music while I have done my homework"

-"I've studied Italian when I was a child"

obrigada