Untread
vt. 返回, 折回, 退回
🗣️ 情景例句
As soon as he left his table.
他刚离开桌子。
It's nice and sweet.
它的味道甜美。
namely 6 million million miles.) Radio waves also travel at the speed of light,
即6万亿英里）。无线电波也是以光速传播的。