I asked a duck what they were doing and he told me they drilled to practice their flying formations when they go south for the winter.

我问一只鸭子它们在做什么，它告诉我它们在练习飞行队形，为冬天去南方做准备。

youdao

While defenders were occupied by intercepting this bogus formation, other formations, flying low, could come in and decimate them.

当把敌方的阻挡机拐骗去进攻这个“编队”的时候，另一个低飞的编队便会来料理他们了。

youdao

Having decided to take part, the ministry was so determined to quash UFO rumours, officials arranged for RAF Lightnings and one US Air Force Phantom to be filmed flying in formations that they said were the basis for the rumours.

BBC: UFO programme 'panic' gripped ministry

Some days, I look down and see hawks flying, and in the winter there are beautiful cloud formations.

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