Light travels basically a foot in a nanosecond. Simple rule of thumb.

光行进的速度是每纳秒一英尺，很简单的经验法则了。

youdao

This form felt light and airy on the foot. So we called it the 'Mojito' as it was rather like a twist of lime skin.

这种方式让脚感到既轻便又通风，之所以我们称它为Mojito，是因为它更像一条扭转的皮带。

youdao

In the pale light of the tunnel, 30-foot fossil traces of lycopsid gleam slickly in the shale roof like alligator skins.

在隧道内黯淡的灯光下，页岩顶部30英尺长的石松化石遗迹就像鳄鱼皮般发出柔滑的光亮。

youdao

Someone else who questions the light foot-print theory is David Rhode.

BBC: Is Obama's drone doctrine counter-productive?

He says that is not a light foot-print.

BBC: Is Obama's drone doctrine counter-productive?

There is a massive, wraparound glass staircase, and dropping down from the 24-foot-tall ceiling is a 12-foot-long "found art" light sculpture made by a local artist with steel rods and old trumpets, toy train tracks and parts of old pistons.

WSJ: The House With a Surprise Inside