[多选题] 使用的滑车应有防止脱钩的( )。使用开门滑车时,应将开门勾环扣紧,防止绳索自动跑出。 (1.0分) A. 保险装置 B. 封口措施 C. 专人监护 D. 专人指挥
参考答案:AB
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第1题: [单项选择]Which sport does the woman like A. Looking for a timetable. B. Buying some furniture. C. Reserving a table. D. Window shopping. 参考答案:C 答案解析:[听力原文] M: Have you a table for four W: Certainly, Sir. A comer table or would you rather be n