Perhaps the most important lesson to be learned is that you simply cannot please everyone.

或许应吸取的最重要的教训是你不可能取悦每一个人。

《柯林斯英汉双解大词典》

There's still one lesson to be learned from the crisis – we all need to better understand the thinking of the other side.

从危机中还要吸取一个教训–我们都需要更好地理解对方的想法。

《柯林斯英汉双解大词典》

Other people may there to help us, teach us, and guide us along our path. But the lesson to be learned is always ours.

人民也许帮助我们，教我们，和那里引导我们沿我们的道路。但教训学会总是我们的。

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The conclusion of this parable seems so violent perhaps because the lesson to be learned from the parable is so uncertain.

这个故事的结尾看起来太残酷了,可能因为这个寓言想要教给我们的东西太不确定。

耶鲁公开课 - 弥尔顿课程节选

The lesson to be learned is not to kill the goose that lays the golden eggs.

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And it's such a great lesson to be learned that - which is to live in the moment.

NPR: Carly Simon's 'Never Been Gone'

If there's a lesson to be learned, its: marry someone whose values and beliefs are in line with your own.

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