此外，信件通常发送到组织外部，而备忘录中通常是内部消息。

Further, letters are usually sent outside the organization, while memorandums are usually internal messages.

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弗兰克递给汤姆发送给麦当劳的邮件副本，“这是一份你的缺点和不足的备忘录，里面还包括对应的正确做法和建议。”

Frank handed Tom a copy of the E-mail he'd sent to McDonald. "This memo details your shortcomings — and corrective measures for them."

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他同时操作两台计算机，一台开着四个窗，负责处理源源不断输入的网上数据；另一台负责发送几百封代表他思想的电子邮件和备忘录。

He works on two computers, one with four frames that sequence data streaming in from the Internet, the other handling the hundreds of E-mail messages and memos that extend his mind into a network.

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