"跑的快"在英语中可以表示为 "run fast" 或 "be fast on one's feet". 这个短语源于人们将快跑和敏捷的身手相联系，即一个人有能力跑得快。

例句：

She is fast on her feet, able to run fast and avoid danger quickly.

(她跑的快，能够快速跑路并迅速避开危险。)

He is known for his speed and ability to run fast, making him a valuable member of the track team.

(他以自己的速度和跑的快而闻名，成为田径队中宝贵的一员。)