Any device can be the dominant at a given moment in the development of literary history.

任何一种方法都可以,在文学发展史的特定时期占支配地位。

耶鲁公开课 - 文学理论导论课程节选

This is a very good way to explain what you are doing at a given moment in time.

这个句型可以很好地解释在某一时刻你正在做些什么。

I'm ~ing 课堂 - SpeakingMax英语口语达人

Now, I've not given you any other example besides the displacement vector, but at the moment, we'll define a vector to be any object which looks like some multiple of i plus some multiple of j.

除了位移矢量之外,我就不再举其他的例子了,但是现在我们要定义一个矢量,可以表示为 i 的倍数加上 j 的倍数

耶鲁公开课 - 基础物理课程节选