（）, 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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

整体式钢筋混凝土板桥承重板的计算单元是（）。

山西大学改为国立后，工学院存在哪些系？（）

钢筋混凝土实心板桥的优点是（）。

简述钢筋混凝土简支板桥的特点

钢筋混凝土板桥涵的特点是什么？

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

简述钢筋混凝土板桥的优缺点及使用条件