lessonn.一节课；一课时；课；教学单元；经验；教训；
短语
be a lesson to对...是一个教训；
give lesson in教授...
The accident taught me a lesson I\'ll never forget.
那事故给我的教训永远也不会忘记。
I\'ve got a piano lesson later today.
今天晚些时候我有一堂钢琴课。
The class settled down and she began the lesson.
全班安静下来她便开始上课了。
