单项选择题
（）(高速)operation and rough handling of covers are dangerous.
A.High-speed B.Low-speed C.Slow-speed D.Quick-speed
单项选择题 In order to avoid shock, reduce the speed by （）(低速控制器)when the cover comes near the stoppers.
单项选择题 When the weather becomes bad, the hatch covers will be （）(关闭).
单项选择题 Don’t operate two or more （）(舱盖)at the same time.
