（）, 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.

When loading or discharging dry mud or cement，crew members should use goggles and（）.

Effects which are dutiable or subject to prohibitions or restrictions should be declared in （）.

（）are liable to be stoten, pilfered or may damaged due to improper handing or stowage.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

摩擦减振器的优点是结构简单，但产生的阻尼基本恒定，不会根据振动幅值的差而自行调节。

摩擦减振器的优点是结构简单，但产生的阻尼（），不能根据振动的强弱自行调节。

超声波是由波源振动而产生，其最低振动频率应大于

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。