VLAN的划分包含哪几种方式？（）
A.基于端口
B.基于MAC地址
C.基于协议
D.基于子网
参考答案：A, B, C, D
Mary bought three pairs of sports shoes the other day, but ______ is expensive. [ ]
A. none of which
B. neither of which
C. none of them
D. neither of them
对接扣件可用在（）。
A.斜杆接长
B.直杆接长
C.立杆双管互绑
D.大横杆接长
