Once at sea, the birds swiftly swam eastwards into the southern Indian Ocean, the investigators found.

一到海里，这些鸟迅速朝东游向南印度洋，调查发现。

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Land that was once at the bottom of the sea now lies around the town in wide, fertile fields; where crabs once crawled, donkeys pick their way.

曾经是海底的陆地现在成了城镇周围广阔肥沃的田野；这里曾经有过螃蟹爬行，现在则有驴子择路而行。

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The rolling sea of clouds you see once you are at the top will remind you how tiny we humans are.

当你登上山顶时，你看到的滚滚云海会提醒你，我们人类是多么渺小。

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Once at sea, the three revealed themselves as Sicilian drug smugglers.

FORBES: Companies, People, Ideas

But even a relatively elderly, second-hand carrier is both expensive to refit and even more expensive to protect, once it is out at sea.

ECONOMIST: China

The Reds' zonal marking system looked all at sea once more and it was no surprise that a failure to pick players up was directly responsible for Unirea's opening goal.

BBC: Unirea 1-3 Liverpool (agg 1-4)