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.

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.

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

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

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

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.

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

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

The vessel has stayed in port for seven days because she needs（）.

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