7、henmakingmoderncameras,peoplebeganto_______plasticsformetal. A.surround B.substance C.stretch D.substitute15.Shewillstopshowingoffifnonotice____ofher.A.istakenB.takesC.willbetakenD.hastaken16.Usually Xiao Li spends____ time doing homework than XiaoChen does.A.