单项选择题
The telegraph is the（）(设备)that connects the engine room and the bridge.
A.gear B.equipment C.engine D.sextant
单项选择题 The captain wants to see the （）.
单项选择题 Echo sounder sends a（） (无线电信号)from the bottom of the ship to the seabed.
单项选择题 Radar is of great help to ship in poor（）(能见度).
