Slowy:We learnt a lesson here. Before we switch on any machine(ma-sheen), we must first read the manual.

这件事教育我们，使用任何机器之前，一定要看说明书。

youdao

They, too, learnt a lesson from the 1991 war.

ECONOMIST: Turkey and Iraq

I'm sure he has since learnt a valuable lesson--that content is expensive.

CNN: ASIANOW - TIME Asia | Asia Buzz: Spot The Fake

Many high-tech firms learnt a similar lesson when the 1995 Kobe earthquake in Japan wiped out some crucial suppliers to the semiconductor industry.

ECONOMIST: Can it ever again be business as usual?