The plane that's ready to take off or is taking off is not such a system.

但即将起飞或正在起飞的飞机并不是这种系统

耶鲁公开课 - 基础物理课程节选

So I'm so happy that it's finally time for us to go to the airport, get on a plane and just take off.

所以当我们终于到了机场，坐上了飞机并起飞后，我真是太高兴了。

I've been 实战 - SpeakingMax英语口语达人

And that's the following. Let's take a particle that is moving in the x-y plane, so that at one instance-- sorry, let me change this graph-- is here--oh, this is bad.

接下来,我们来看一个物体,在 x-y 平面内运动,在这个例子中,对不起,我要重画一下这个图,在这里,这画得不好

耶鲁公开课 - 基础物理课程节选