whiskered terns travel thousands of kilometers 须浮鸥会飞行数千公里
600 meters deep and covering 10,000 square kilometers. 深达600米 面♥积♥达一万平方公里
compacted to form permanent ice sheets several kilometers thick. 压缩成了几千米厚的永久性冰层
Today, they are 2,500 kilometers long, 如今该山脉长2500公里
they pierce the surface at close to 90 kilometers an hour. 以接近每小时90公里的速度刺入水面
Able to rapidly accelerate to 50 kilometers an hour... 它能够很快加速到每小时50公里
Every living thing within a thousand kilometers 一千公里范围内的一切生物
is tumbling towards Earth at 100,000 kilometers per hour. 正以每小时10万公里的速度坠向地球