The reason they have not is that in the normal, two-legged gait the foot is in contact with the ground for only around one-tenth of a second, 0.05 seconds less than when hopping.

之所以没有出现这样的情况是因为在正常情况下，双腿跑动时，脚和地面的接触时间仅有十分之一秒，比跳跃时少0.05秒。

It was as though the days, flying horror-struck from the shrouded image of the one inscrutable day, gained assurance as the distance lengthened, till at last they fell back into their normal gait.

就好像日子， 从一个神秘的日子笼罩的形象中惊恐地飞过， 随着距离的拉长而获得了保证， 直到最后他们回到了正常的步态。