line trace mill

例句：

1. 1.The detective used a line trace to find the thief's hidden location.
   侦探使用线状追踪来找到小偷隐藏的位置。
2. 2.The scientists followed the line trace of the chemical reaction.
   科学家们跟踪了化学反应的线状追踪。
3. 3. The artist drew a line trace on the canvas to guide the brushwork.
   艺术家在画布上用线状追踪来指导笔触。