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.

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

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

Radiotelephony communication or radio telex communication or both will be carried out by terrestrial or satellite means,（）the equipment fitted on ship and the area in which the incident occurs.

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.

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

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

On-scene communications will normally take place between（）.

The advantage of geostationary satellites is（）.

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