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.

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

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

Stations in the United States of America are grouped by states arranged in the alphabetical order of their（）.

SafetyNet is an international service for the broadcast and automatic reception of MSI by means of direct-printing through（）system.

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

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

Particular care should be（）in selecting CESs in areas where Ocean Regions overlap.

All coast radio stations（）DSC installed for VHF and HF.

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.