（）, or drum is used for hauling in or letting out the wires or ropes which will fasten the ship to the shore.

A salvor may be（）the whole or part of the payment due under Salvage Convention to the extent that the salvage operations have become necessary or more difficult because of fault or neglect on his part or if the salvor has been guilty of fraud or other dishonest conduct.

The （） is used for hauling in or letting out the wires or ropes.

Vessels must be（）valid certificate of nationality or certificated of registry or license.

压入（潜没）式泵房的优点是（）。

潜没式泵房的缺点有（）

矿井主排水泵房分吸入式泵房，（）泵房。

矿井主要泵房有哪些规定？

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

冷凝工段泵工岗位有哪些技术规定？

矿井泵工每班都巡回检查，检查时间为（）小时/次。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。