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.

Monitoring is especially important in a highly automated system which is dependent on careful（）procedure and format.

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.

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.

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,（）.

Can MF/HF radiotelephone receive the MSI sent from the coast stations alone?（）

As each MSI message will have a unique identity, the printing of messages already received correctly is（）.

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