单项选择题
Are you the sailor on duty?（）
A. Yes, you are. B. You are right. C. Yes, I am. D. Not at all.
单项选择题 The captain of a ship can be also called （） .
单项选择题 ---What is your rudder? ---（）.
单项选择题 ---Ease helm. ---Ease helm. （）.
