商务谈判讲求谈判的经济（）。
A.效益
B.效率
C.效果
D.效用
参考答案：A
The mother, as well as her two daughters, ____ to the theatre with some friends this evening.
A．are going
B．were going
C．is going
D．was going
轨道车收车后应做哪些检查工作？
