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 （）.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

低淬透性冷作模具钢的变形比低变形冷作模具钢（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

校正弯形时，材料产生的冷作硬化，可采用（）方法，使其恢复原来的力学性能。

在冷作模具材料中，以下哪些材料属于高碳高铬模具钢（）

冷作模具钢Cr12MoV平均含钼量小于1．5%。

冷作模具钢和热作模具钢的都是高碳钢。