残留似乎是自我产生的 但它不会自我消除.删除你能够删除的 时常整理你的参考文件 当它失去时效 失去价值.

Residue seems to self-generate but it doesn't self-destruct! Delete what you can to begin with, and purge your reference files regularly, as things get out of date and lose their value to you.

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天气状况变幻莫测，使得飞行前的天气信息失去时效。

Weather conditions can change quickly, making preflight briefings obsolete.

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如未在两年期间提起司法诉讼或仲裁，根据本公约的任何诉讼即失去时效。

Any action under this Convention is time-barred if judicial or arbitral proceedings have not been instituted within a period of two years.

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