开往美国的货运飞机必须符合特定的安全要求，其中包括必须通过安全扫描以及工作人员的核定，还得向当局提前发送舱单。

Cargo shipped on planes to the United States must meet certain security requirements, including for screening, vetting of personnel in the facilities and providing advance manifests to authorities.

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比如，拥有较大飞机的人，只需要提前24小时提交他们的飞行计划——而不像单引擎飞机之类的较小飞机的拥有者那样需要提前好几个星期。

Owners of larger jet planes, for example, need only submit their flight plan 24 hours in advance - as opposed to weeks in advance for smaller craft like single-engine planes.

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还有，信用卡公司须在欠款到期前，至少提前二十一天递出结算单。

Also, companies will have to send out billing statements at least twenty-one days before a payment is owed.

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