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.

Radio beacon can be activated（）in case of distress.

Ship-to-ship distress alerting should be conducted by（）.

At least two two-way VHF radiotelephone apparatus shall be provided on every cargo ship of（）tons gross tonnage and upwards but less than 500 tons gross tonnage.

Distress traffic is the communication（）between the station in distress and the ships, aircraft, coast radio stations, coast earth stations and rescue centers participating in the rescue work.

Before GMDSS, if the radio officer on board is serious ill,（）.

The priority of EGC messages is classified by（）.

Radio communication（）for many years and helps to save tens of thousands of lives.

The quality of EGC messages is（）affected by the position of the ship, the time of reception and climatic conditions.

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