4、ourfriendschooseyou?Haveyougotagoodfriendyourparentsdon'tlike?21. Manyteenagersthinktheir_______knowthembetterthantheirparentsdo.A.friends B. teachers C.brothersandsisters D. classmates22. Whenteenagersstayalone,theusualwayofcommunicationisto_________.A.gototheirfriends B.talkwit