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單項(xiàng)選擇題

The purpose of the GMDSS is to（）safety of life and property at sea all over the world.

A.promote
B.improve
C.guarantee
D.both A and B

你可能感興趣的試題

單項(xiàng)選擇題

The first communication satellite was used for the purpose of（）.

A.taking the place of the radio system
B.introducing a new life-saving system
C.saving the vessels in distress
D.improving the communication on land

單項(xiàng)選擇題

A sailor on board（）from appendicitis and required operation immediately.

A.was suffering
B.is suffering
C.has suffered
D.has been suffering