单项选择题
船舶的舱盖有多种类型。（）
A. There are several types of hatch covers on board ship. B. There are several types of hatches on board ship. C. There is one type of hatches on board ship. D. There is one type of hatch covers on board ship.
单项选择题 开关舱的工作通常是由船员来做。（）
单项选择题 装卸货之前，打开舱盖。（）
单项选择题 The running wheel runs along （）on top of the hatch coaming.
