These so-called surface deliveries have been the crucial method by which booksellers have sold books to foreign markets because the cost is about one-third that of air mail.

这些所谓的水面运送方式，一直是书商们将书卖往海外市场的主要方法，因为它的花费只有航空邮件的三分之一。

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If they were really serious about this, they would've pushed back the cancellation of surface mail until they could incorporate these other standards.

如果他们真的关心此事，那么直到他们能够将其他标准包含进来，他们也许就不会接受取消水运邮政业务。

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NASA recently released a stunning image showing the surface of Mars in extraordinary detail, including a myriad of shapes and textures seen as carbon dioxide or water frost, the Daily Mail reported.

据英国《每日邮报》报道，美国宇航局近日公布了一张火星冬季的照片，展现了火星表面无数令人惊叹的地貌特征和结构，其中包括二氧化碳或者水形成的霜。

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One consignment of surface mail mouldered on the docks for a year.

ECONOMIST: Stamp duty

Now think of Internet electronic commerce as the e-mail equivalent of traditional commerce's surface post.

ECONOMIST: Eventually, bigger means different