The captain has （）ashore.

单项选择题When a ship is in port, （）must keep a gangway watch.

A.officers
B.crew members
C.sailors
D.motorman

单项选择题When a ship is in port, the sailor on duty （）a gangway watch.

A.has
B.keeps
C.looks
D.takes

单项选择题Hang national flag upside down should be strictly （）.

A.prohibit
B.prohibited
C.prohibiting
D.prohibits

单项选择题When you hoist national flag, you should hoist it（）.

A.quickly
B.rapidly
C.slowly
D.speedily

单项选择题After a ship leaves a foreign port, you should （）that country’s national flag.

A.hoist
B.lower
C.hoisted
D.lowered