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来源：雅诚德英语网
How do birds and bats and other flying beasties manage to get off and stay off the ground?
鸟类、蝙蝠和其他会飞的生物是如何离开地面、保持飞行状态的呢？
How do birds and bats and other flying beasties manage to get off and stay off the ground?
鸟类、蝙蝠和其他会飞的生物是如何离开地面、保持飞行状态的呢？