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

In case a ship is in emergency or distress in any of 4 areas, it is required to use the continuous（）alert.

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

The priority of EGC messages is classified by（）.

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

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

Every lifeboat which is fitted with a fixed two-way（）radiotelephone apparatus with an antenna which is separately mounted shall be provided with arrangements for sitting and securing the antenna effectively in its operating position.

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.

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