Despite the rising importance and great convenience of the gyrocompass,the magnetic compass still retain its importance because of its（）.

The company should establish and maintain procedures to control all documents and date which are relevant to（）.

According to the relevant regulation, lifeboat should be powered by（）.

When steering by autopilot,how often should the steering be checked?（）

（）is where the crew eat their meals.

When the wave period and the apparent rolling period are the same（）.

The helm command PORT TWENTY means（）.

Berthing means bringing a vessel to her berth until（）.

It is dangerous for vessels without the operational radar（）the estuary.

The force resulting from the earth’s rotation that causes winds to deflect to the right in the Northern Hemisphere and to the left in the Southern Hemisphere is called（）.