常用布尔算符有：and、or、not等，当采用同义词进行检索时应当选用的算符是？

常用切削加工齿轮齿形的方法有（）。其中，加工精度和生产率高，应用广泛，但不能加工齿条和内齿轮的是（）。

按照齿轮齿形的形成方法，齿轮刀具分为（）大类。

齿轮齿形的加工方法主要有（）；加工双联齿轮、内齿轮、齿条应采用（），加工斜齿圆柱齿轮应采用（）。

展成法加工齿轮是利用齿轮刀具与被切齿轮保持一对齿轮啮合运动关系而切出齿形的方法。

Every deliberate act of wrongdoing by the master or any of the crew against the ship or cargo，without the authorization or privity of the Shipowner or his agent，is（）.

（）, 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。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。