A hard lesson certainly, but also a shocking wake up call.

它的确是一个沉重的教训，但也是一次令人难忘的警钟。

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It is a hard lesson to learn, but we must all learn it.

学习这一课并不容易，但却是我们所有人的必修课。

youdao

Duality has been a hard lesson to go through at the levels you are in, but your progress up the spiritual ladder has been phenomenal.

在你们所处的水平上，二元性是一堂需要去通过的艰苦的课程，但是你们在灵性的阶梯上的进步一直是显著的。

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Together, they are teaching us a hard lesson: In medicine, nothing comes for free.

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It was a hard lesson learned, but here it is: Knowledge is not power.

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Some experts are therefore saying that the German people may have to learn a hard lesson.

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