航海英語船舶結(jié)構(gòu)基本知識(shí)單項(xiàng)選擇題每日一練(2019.01.11)

來源：考試資料網(wǎng)

1 Which space（s）is（are）deducted from gross tonnage to derive net tonnage（）.

2 While cranking out a quadrantal davit，slippage of the quadrant due to excessive wear or failure of the teeth in the quadrant will cause the（）.

3 The inner bottom is the（）.

4 The joint formed when two steel plates are placed end-to-end is called a（）.

5 Why is it necessary to extend ventilators of gasoline powered vessels to the bilges（）.