舞台成像灯、舞台回光灯、舞台聚光灯以及媒体电脑灯属于舞台常规灯具。（）

如何改变聚光灯的圆锥体角度？（）

光栅检测装置主要由电源、聚光镜、标尺光栅、指示光栅和（）组成。

透射式幻灯机是根据（）原理设计的，即光源发出的光线经聚光镜会聚照亮幻灯片，再通过放映镜头在银幕上形成（）的幻灯片图像。

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。

按照结构特征与测量方法不同，常用汽车前照灯校正仪可分为聚光式、（）、（）和（）四种类型。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。