S old iers in ancient Greece used polished shields to send battle orders to each other over vast distances in the form of flashes of sunlight.

早在古希腊，相距较远的士兵通过利用抛光的盾牌来产生闪光信号传达作战命令。

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Soldiers in ancient Greece used polished shields to send battle orders to each other over vast distances in the form of flashes of sunlight.

古希腊士兵用擦得锃亮的盾牌，通过反射太阳光，相互之间长距离传送作战命令。

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The downturn in the air travel market over the past couple of years has led to a fierce battle between Boeing and Airbus to win new orders.

BBC: Airbus wins US order