Swallows fly to the south before winter, and fly back in spring.

燕子冬天之前飞到南方，春天又飞回。

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In winter, many birds fly to the south, because they need to find a warm place to live, but they will fly back in spring.

冬天，很多鸟儿会往南飞，他们需要给自己找个温暖的地方生存，但是到了春天，它们又会飞回来。

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Arctic terns, being true long-distance migrants, they nest in coastal wetlands of northern Europe but fly south for thousands of miles to spend the European winters in Antarctica.

北极燕鸥是真正的长途迁徙者，它们在北欧沿海湿地筑巢，但会向南飞行数千英里，在南极洲度过欧洲的冬季。

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But,during the past three years, some have failed to fly south.

VOA: special.2010.03.02

Afriqiyah said its crewmembers were Libyan. Officials in South Africa reported most aboard the flight had planned to make a connection in Tripoli and fly on to various destinations in Europe.

VOA: standard.2010.05.12

Josh was due to fly back to South Carolina on the evening of this interview but he said he had enjoyed a fantastic experience in south Wales.

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Football fans planning to fly out to the World Cup in South Africa could also be affected, with the last of the five-day stoppages beginning on the weekend before the tournament starts.

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Coach Marcelo Lippi has opted to leave out several household names for this final friendly before they fly out to South Africa for the Confederations Cup.

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