translation.en: Humans and soaring birds have found nature to be generous in providing replenishable energy. Sailplanes have flown over 1,000 miles, and the altitude record is over 50,000 feet.
translation.zh: 人类和飞鸟已经发现大自然在 提供持续能力方面是非常慷慨的。滑翔机飞行了 超过1，000英里，海拔记录超过50，000英尺。