When weather became bad, the insect depended ground flight more, the barn swallow wanted to eat an insect, so low fly.

天气转坏时，昆虫多靠地面飞行，燕子想吃昆虫，所以低飞。

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Unlike high altitude aircraft, helicopters aren't so vulnerable to being seen by radar, as they fly low and are often hidden by the terrain. The big issue is the sound.

与在高空飞行的飞机不同，直升机不容易被雷达发现，因为它的飞行高度较低，且常常被地形所隐藏，因此最大的问题是噪音。

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I love jets. So I don't mind the noise and how low they fly.

我喜欢战斗机，所以我不介意这噪音以及它们的低空飞行。

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Geosynchronous satellites are so distant that their images aren't sharp, while low-earth orbit satellites, which fly as low as 100 miles, can feed information only when they pass over an area of interest.

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