因为商队只能通过水路和山脉进入沙漠，贸易就成为了中东城市的主要经济支柱。

Trade was the mainstay of the urban economy in the Middle East, as caravans negotiated the surrounding desert, restricted only by access to water and by mountain ranges.

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公元前1世纪，我国商队通过“丝绸之路”与西方建立了贸易往来。此时人类亦可以对织物进行染色。

In the 1st century B. c., our country caravan passed "the Silk Road" to establish the trade with the West. At the same time, the humanity also can dyeing on the fabric.

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