Réponse :
1) This is the girl who I told you about last week.
2) I lived in a house which/that was near the school.
3) This is the boy who got his locker destroyed.
4) There is a new shop in town which/that sells sports equipment.
Explications :
Pronom relatif apres une personne: who
apres un objet ou toute autre chose: which ( ou that eventuellement)
