I'm a teacher with 21 years' experience.

我是一个有21年经验的教师。

《柯林斯英汉双解大词典》

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》

Experience is the best teacher.

经验是最好的老师。

youdao

She's been an elementary school math teacher for almost 30 years, and says introducing this new curriculum has been an exciting experience.

VOA: standard.2010.08.10

When Regilene Cunha entered her first classroom as a teacher she had zero practical experience.

BBC: Booming Brazil held back by education gap

She has previous experience as a teacher and small business owner, and serves on North Carolina's Local Government Commission, and Economic Development Board.

CNN: Helms departure opens Senate race in N.C.

Of course, experience is the ultimate teacher of the differences between smart and wise.

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