Tractrix
等切面曲线, 曳物线
🗣️ 情景例句
OK, here are the walnuts.
嗯， 核桃在这 。
Modesty is not only and ornament, but also a guard to virtue.
谦逊不仅可增添光彩也可以维护美德。
I'm all set.
我都准备好了。