单项选择题
In order to pay out or slack a mooring line which is under strain，you should（）.
A.sluice the line B.surge the line C.stopper the line D.slip the line
单项选择题 In order to maintain a safe speed at all times，any necessary alterations of speed must（）.
单项选择题 In order to detect rot in manila lines，you should（）.
单项选择题 In heavy seas the helmsman should steer the survival craft（）.
