环境决定论的典型代表是（）
A、洛克
B、华生
C、格塞尔
D、高尔登
E、孟禄
参考答案：A, B
2B+D用户线路在用户端与交换机之间传递的是（）。
Email, as well as telephones, ________an important part in daily communication. [ ]
A. is playing
B. have played
C. are playing
D. play
