单项选择题
The emergency alarm is sounded on （）(汽笛) according to master’s order.
A.VHF B.whistle C.broadcast D.sextant
单项选择题 There is a smell of gas in the hold. You must wear your （）(氧气面罩).
单项选择题 Prepare for （）(弃货) cargo.
单项选择题 Post two lookouts with （）(望远镜).
