er是一个元音，它的发音主要是舌尖起作用，所以称舌尖元音，又因为它发音时将舌头卷起，所以又称卷舌元音。

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。

不同的元音是口腔的不同形状决定的。所谓口腔的形状就是指舌位的高低、前后和嘴唇的圆与不圆。

形状公差指理想要素对被测单一实际要素的形状所允许的变动量

检验形状误差时，被测实际要素相对其理想要素的变动量是形状公差。

验形状误差时，被测实际要素相对其理想要素的变动量是形状公差。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。