Hawking's main concern was that a fleet of alien spacecraft could turn up wanting to strip mine the Earth for its bountiful resources.

霍金的主要忧虑是一队外星人飞船舰队可能会突然出现，想要将地球上储量丰富的矿藏洗劫一空。

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Shipping is one of Greece's main industries, with Greeks controlling nearly 20 percent of the world's merchant fleet.

船运也是希腊支柱产业之一，该国控制了全球商船队的接近20%。

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The galleon was the main ship in a treasure fleet carrying gold, silver and other valuable items from Spain's American colonies to King Philip V.

这艘帆船作为主船队，载满着从西班牙在南美的殖民地进献给西班牙国王费利佩五世金银珠宝。

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The service will run double deckers on the main airport route, with the bulk of the remaining fleet made up of slimline single-decker buses.

BBC: Jersey bus drivers are to be interviewed by new operator

The council said its fleet of gritters would be out throughout the night treating main roads and major bus routes.

BBC: Gritters out in Staffordshire after ice warning