Experience is the best teacher.

经验是最好的老师。

youdao

He's the best teacher, even though he has the least experience.

他虽然经验最少，却是最出色的老师。

《牛津词典》

You are the best teacher ever!

您是天底下最好的老师！

youdao

When I created Team 2, my first pick was the best teacher I could find.

CNN: Commentary: Good schools aren't only for rich kids

Haiti has been the best teacher I've ever had (and that's saying a lot).

FORBES: Magazine Article

As Asia faces its biggest crises since Independence, adversity may again prove the best teacher.

CNN: CENTURY OF LIBERATION