请问这句英文是什么意思TradewasthemainstayoftheurbaneconomyintheMiddleEast,ascaravansnegotiatedthesurroundingdesert,restrictedonlybyaccesstowaterandbymountainranges.

Question

请问这句英文是什么意思
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.

Answer 1

1.（对外）商贸是中东地区都市经济的至要命脉,（其作用）就像商队跋涉穿越周匝大漠,而商旅路线仅由取水之道和连绵山脉（所）决定.
2.商业交易之于中东地区城市经济的命脉地位,（就）好比商队穿越浩瀚沙漠,而水源通道和延绵山脉决定商队如何跋涉.
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