信封扁平，装折叠纸的容器，尤其用来装信。

A flat, folded paper container, especially for a letter.

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欢迎来到一分钟英语。信封是一种扁平的容纳物，用来送信的。

Welcome to English in a minute. An envelope is a flat paper container used to send a letter.

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阅读我们关于用于紧急运输较重的文件的扁平的快递信封的信息和规格。

Read our information and specifications about flat express mailers used for urgent shipments of heavier documents.

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