语言学习的根本法则就是“用进废退”。

One fundamental rule of language learning is: "Use it, or lose it. ""

youdao

但不论细节如何，这种“用进废退”的情形显然确凿无疑。

Regardless of the details, though, this would appear to be a clear case of "use it or lose it".

youdao

脑运动有：用进废退、适度用脑、整体开发、身心互动和脑体交替等规律。

The principle of brain movement have: Progress on use and retarding on waste, moderate use integral exploit, physical and mental alternation.

youdao

And then your hostess walks in with the turkey in a tray, and says, "I killed the last cockroach."

然后主人用托盘托了一只火鸡进来说,我刚刚把最后一只蟑螂拍死了“

麻省理工公开课 - 计算机科学及编程导论课程节选

And to see that I've written another version of this, which I'm going to use here, where I'm going to give it a little indentation.

我已经写另一个版本的代码,我将把它用在这儿，我会在这儿加一点儿缩进。

麻省理工公开课 - 计算机科学及编程导论课程节选

It involves putting a needle, a fairly large needle into usually one of the pelvic bones and collecting marrow from which is tissue that's deep inside those bones.

先要用针头,相当大的针头刺进你的盆骨,然后进行收集,这些在骨头深处的骨髓

耶鲁公开课 - 生物医学工程探索课程节选