official letter

基本解释

New officials also had little experience in writing official letters or documents.
新官员也不太懂怎么书写公文函件。
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Travel by airplane was once considered a privilege for people with official letters of recommendation.
随着民航事业的迅速发展，以往只有持介绍信才能享受的飞机，如今成为寻常百姓的交通工具。
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This, however, only solved the problem of official letters, and civilians were left without any means of written communication.
这只解决了递送公文的问题，老百姓寄信还是没有办法。
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