使用阴阳电离子仪时，导药钳在皮肤上移动要（）。
A.缓慢
B.快速
C.有力度
D.有节奏
参考答案：A
— Look! The black clouds are gathering, which indicates that it __________ rain soon.
— Yes, black clouds are the _________ of the rain. [ ]
A. is going to; signal
B. will; mark
C. is gong to; sign
D. is to; sign
经营指导书较口头指导形式更为规范，但不利于痕迹化管理（）
