Donahoe reminds customers that December 17th will be the busiest day for mailing CARDS and packages, and the 22nd will be the last day for guaranteed express mail Christmas day delivery.

多纳霍提醒顾客，12月17日是寄卡片和包裹最忙碌的日子，而要保证圣诞节收到快递，则必须要在12月22日前寄出。

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In these cases, ground delivery may be guaranteed overnight, and is generally cheaper than second-day air.

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Amazon avoids much of that with guaranteed delivery to its lockers, often housed in locations operating 24 hours a day.

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