This accident affords us a useful lesson.

这个事故为我们提供了有益的教训。

《新英汉大辞典》

We must draw a useful lesson from it.

我们必须从中吸取有益的教训。

youdao

But another academic market offers a useful lesson.

但是另外一个学术市场提供了有益的经验教训。

youdao

Each article, ideally, should be something of a morality tale from which the reader comes away thinking there is a useful lesson.

FORBES: Fact and Comment

And even the short ones should be something of a morality tale, leaving the reader feeling that there's a useful lesson to be learned.

FORBES: Magazine Article

There is a common fallacy, not least in Germany, that dropping the Greeks would be a fairly costless way to teach a useful lesson.

ECONOMIST: The euro