Teach your teenager that the family phone is for the whole family.If your child talks on the family's telephone for too long，tell him he can talk for 15 minutes，but then he must stay off the phone for at least an equal period of time.This not only frees up the line so that other family members can make and receive calls，but also teaches your teenager moderation(节别)or if you are open to the idea，allow your teenager to have his own phone that he pays for with his own pocket money or a part­time job.