单项选择题
When a ship is in port, （）must keep a gangway watch.
A.officers B.crew members C.sailors D.bosun
单项选择题 A （）should be placed on the gangway.
单项选择题 Please fill in this visitor’s （）.
单项选择题 -Will you take me to see your chief officer? -Sorry, he has gone （）. Would you like to leave a message for him?
