This is a painful lesson.

这是一个惨痛的教训。

youdao

This has been a painful lesson to me.

对我来说，这是一个惨痛的教训。

youdao

This has been a painful lesson to me.

这对我是一次痛苦的教训。

youdao

U.N.Secretary General Ban Ki-moon told BBC television that was a painful lesson, and the United Nations will make changes for next month's vote.

VOA: standard.2009.10.21

The painful lesson of budget deals past is: never mind the official agreement.

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History has taught us a painful lesson that we are poised to learn all over again.

CENTERFORSECURITYPOLICY: Doing in defense

Indeed, that is a painful lesson anyone who borrowed against their home to purchase goods and services has learned.

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