电子商务具有高效性、协作性及以下哪些特性（）
A、安全性
B、可扩展性
C、集成性
D、方便性
参考答案：A, B, C, D
The layer thought it unfair for his client to _______ ten years in prison just because he had helped
the robbers escape. [ ]
A. to be sentenced
B. to sentenced to
C. to be sentenced to
D. have sentenced to
楼宇设备自动化系统设计的基本步骤？
to be sentenced