That's another way of saying maintaining velocity if it's not acted upon by a force.

这就是不受外力作用时,速度保持不变的另一种说法

耶鲁公开课 - 基础物理课程节选

It was supposed to maintain the convertibility of the currency into gold.

它的作用在于保持,货币与金子间的转换。

耶鲁公开课 - 金融市场课程节选

The fact that you don't need a force for it to move forever at a given speed in a given direction, that's not obvious, because in daily life you don't see that.

对于物体不需要力的作用就能保持,确定的速度和方向持续运动这一事实,它并非显而易见,因为在日常生活中你看不到这种情况

耶鲁公开课 - 基础物理课程节选

And fairly soon into the conversation I demonstrated some principle that you've probably learned in your physics class having to do with an object at rest remaining at rest unless acted upon by a force.

很快，在交谈中,我就展示了一些原理,可能你们在物理课上学过,要使静止的物体保持静止,必须有外力作用。

耶鲁公开课 - 心理学导论课程节选

What makes the law surprising is that if I only gave you half the law, namely every body will remain at rest if it's not acted upon by a force, you will say, "That's fine. I accept that, because here's something, you leave it there, it doesn't move.

这条定律妙就妙在,如果只看定律的前半段,即,如果物体不受外力作用,将保持静止状态,你肯定会觉得,"这没什么,我能理解,因为你把一个物体放在那里,自己肯定不会动

耶鲁公开课 - 基础物理课程节选

The Law of Inertia says that, "If a body has no forces acting on it, then it will remain at rest if it was at rest to begin with, or if it had a velocity to begin with, it will maintain that velocity."

惯性定律就是,"如果一个物体不受外力作用,那么静止的物体依然保持静止,如果物体有个初速度,那么就保持此速度不变"

耶鲁公开课 - 基础物理课程节选