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（）.

（）is halfway between the forward and after perpendiculars and is reference point for vessel construction.

A tide is called diurnal when（）.

The helm command PORT TWENTY means（）.

（）is where the crew eat their meals.

Manoeuvring information can not be obtained from（）.

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

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

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

Bales close to the deckhead should be covered to prevent（）.