retracing 释义 折回 返回 例句 1·Retracing my steps was certainly not an option. 回顾我的脚步并不是个办法。 2·We're retracing the route of a deep explorer mission. 我们将折回一个深入的探险路线中去。 3·Which figure CANNOT be drawn without lifting the pencil or retracing ? 不用虚线和回描,那幅图不能被画出?