单项选择题
Weigh anchor and（）(留)one shackle in water.
A.stay B.keep C.leave D.have
单项选择题 Anchor（）(垂直).
单项选择题 On a vessel, lines are（）(挽牢) on bitts.
单项选择题 Make sure that the windlass is（）（脱开离合器）.
