General Grant was beginning to learn an important lesson of the war.

VOA: special.2009.11.26

And this is a hugely important lesson to learn.

这么问自己，这是不是一个隐藏的。

麻省理工公开课 - 计算机科学及编程导论课程节选

Grant was beginning to learn an important lesson of the war.

VOA: special.2009.12.03

These are students who felt under enormous pressure to perform, and I want to underscore the word 'perform,' as opposed to 'learn.'" She says the hardest lesson for society may be that young people will grow up lacking interest in learning.

VOA: special.2011.07.14

It was Arabs who did this to other Arabs." Smith believes that is the main lesson American policymakers should learn: that Arabs today are divided against themselves.

VOA: standard.2010.03.18