Highly active file systems may require around 15% of space.

高度活跃的文件系统可能需要大约15%的空间。

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You must cancel the active file transfer prior to sending a file.

发送文件之前，您必须取消正在进行中的文件传送。

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So the special active file keeps track of whatever you missed.

因此这些特殊的文件保持着它的轨迹。

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During his 2012 WWDC keynote presentation, Tim Cook announced Apple has more than 400 million active credit cards on file.

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Whenever new files are added, or changes are made to an existing file within the Active Copy enabled folder, these files are automatically copied to a chosen destination folder.

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With over 400 million active credit card accounts on file, Apple had a prime opportunity to convert its customers using a sleek mobile payment system tied to the iPhone.

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