（）, 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 （）.

打开一个已有文件，然后在文件末尾添加信息，正确的打开方式为（）。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

计算机Microsoft Office PowerPoint软件的文件扩展名为（）。

计算机Microsoft Office Power Point软件的文件扩展名为（）。

打开一个数据库文件的同时打开以“姓名”为关键字的单一索引文件，要求查找姓名为“张伟”的教师，使用命令( )。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。