altitude

The pilot announced that the plane was cruising at an altitude of 30,000 feet.

(Chinese) 飞行员宣布飞机正以三万英尺的海拔高度巡航。

Athletes often train at high altitude to increase their lung capacity and endurance.

(Chinese) 运动员经常在高海拔地区训练，以增加肺活量和耐力。