A. Bosun, why do we open hatch covers?
B. Officer, why do we open hatch covers?
C. Bosun, why do we close hatch covers?
D. Bosun, why do we open hatches?

A. After operation, start the electric motor.
B. Before operation, stop the electric motor.
C. Before operation, start the electric motor.
D. After operation, stop the electric motor.

A. To avoid shock, reduce the speed of moving hatch cover by inching control.
B. To avoid shock, reduce the speed of moving hatch cover by control levers.
C. To avoid shock, reduce the position of moving hatch cover by inching control.
D. To avoid shock, reduce the course of moving hatch cover by control levers.

A. High-speed operation and rough handling of hatches are dangerous.
B. Low-speed operation and rough handling of hatches are dangerous.
C. Low-speed operation and rough handling of hatch covers are dangerous.
D. High-speed operation and rough handling of hatch covers are dangerous.

A. We dismantle the jumbo boom twice a voyage.
B. We dismantle the derricks once a voyage.
C. We examine the derricks once a voyage.
D. We dismantle the heavy derricks once a voyage.

A. Each hatch consists of two panels.
B. Each hatch cover consists of two panels.
C. Each hatch consists of two or more panels.
D. Each hatch cover consists of two or more panels.

A. These hatches are usually driven by electric or hydraulic power.
B. These hatch covers are usually driven by electric or hydraulic power.
C. These hatch covers are usually driven by electric.
D. These hatch covers are usually driven by hydraulic power.

A. There are several types of hatch covers on board ship.
B. There are several types of hatches on board ship.
C. There is one type of hatches on board ship.
D. There is one type of hatch covers on board ship.

A. The work of opening and closing hatches is usually done by crew members.
B. The work of opening and closing hatch covers is usually done by crew members.
C. The work of opening hatch covers is usually done by crew members.
D. The work of closing hatch covers is usually done by crew members.

A. After loading and discharging, hatch covers will be opened.
B. After loading and discharging, hatch covers will be closed.
C. Before loading and discharging, hatch covers will be opened.
D. Before loading and discharging, hatch covers will be closed.