（）by an ice-breaker, it is important to maintain a continuous listening watch on the appropriate VHF channel and to maintain a proper look-out for sound and visual signals.

In case a ship is in emergency or distress in any of 4 areas, it is required to use the continuous（）alert.

If the beacon is mounted at a wrong place, it may（）by sea water, chemicals, exhaust and vibrations.

International Navtex service means the coordinated broadcast and automatic reception on（）khz of maritime safety information by narrow-band direct-printing telegraphy using English language.

COSPAS-SARSAT is intended to be used for（）.

Every lifeboat which is fitted with a fixed two-way vhf radiotelephone apparatus with（）which is separately mounted shall be provided with arrangements for sitting and securing the antenna effectively in its operating position.

We consider（）send a helicopter with medical facilities to the distress area.

（）will form the basis for distress alerting and safety calling.

The priority of EGC messages is classified by（）.

By using（）system a ship can send a distress message and know with certainty it will be received.