浇口的类型可分点浇口、侧浇口、（）浇口、中心浇口、潜伏式浇口、护耳浇口六类。

单分型面注射模的浇口可以采用直接浇口、（）、侧浇口、环形浇口、轮辐式浇口和（）。

侧浇口又称边缘浇口或标准浇口，不根据其变异的浇口类型是（）。

出现困难件的主要原因是（）。

离心泵填料寿命过短的原因是由于（）。

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.

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。

压铸过程中，如果模温高，则使铸件冷却缓慢而晶粒粗大，容易导致坯件出现下列问题（）

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。