具备什么样的条件承诺才有效？

具备什么样的条件要约才有效？

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。

特种作业人员具备什么资格才能上岗作业？

提出“作为传递社会文化经验的教学应在儿童心理发展中起主导作用，只有那种走在发展前面的教学才是良好的教学”的是（）

作为一名师范生或在职教师除了应具备各种教学技能外，还应具备较高的对（）、（），只有这样才具备了进一步提高教学技能和研究教学艺术的条件。

逻辑运算符（AND、NOT、OR）的运算顺序是AND→OR→NOT。