This is why a person may walk in an arc when he sets out in a straight line.

这就是一个人在出发时本来是想走的直线，结果却走成了一条弧线的原因。

youdao

Then you know that it will rarely travel in a straight path. It will travel, instead, in some kind of arc, or curve.

本句翻译：那么，你就会知道小汽车几乎很少顺着直线跑，而是以弧线或者曲线的方式前行。

youdao

In character recognition, a straight line or arc used as a segment of a graphic character.

在字符识别中，用以构成图形字符中某一小段的直线或弧。

youdao

They never trailed, held the league's best team from 3-point range to 4-of-25 shooting from beyond the arc, and bolstered their NCAA tournament credentials by beating Duke for the second straight time.

NPR: Wells Leads Maryland To 83-74 Upset Of No. 2 Duke