Efficient fire-fighting drill demands the full （）of persons in all departments of the ship.

单项选择题The signals that will be used for emergency should be clearly （）.

A. set out
B. set off
C. get off
D. cut off

单项选择题The fire drill is （）. You are dismissed.

A.finish
B.finished
C.begin
D.beginning

单项选择题Lower the （）ladder.

A.embark
B.embarkation
C.disembark
D.B+C

单项选择题The boat is （）to the water surface.

A.down
B.top
C.lower
D.up

单项选择题Ready for （）the boat.

A.lower
B.lowering
C.lowered
D.topped