根据病毒壳粒数目及排列方式不同，病毒核衣壳结构划分为3种类型，即二十面体立体对称型、螺旋对称型和（）。

所有病毒都呈二十面体对称或螺旋对称结构吗？

二十面体对称的病毒粒子的五邻体位于（）。

病毒由（）和（）组成，病毒衣壳有三种对称性构型，即立体对称型，（）型和复合对称型。

二十面体（Icosahedron）

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。