But ultimately, the best way, the optimal way spreading happiness is to work on your own happiness, because then you are leading by example.

但最好的方法，传播快乐的最佳方法是努力争取自己的快乐，因为那时你就成为榜样。

哈佛公开课 - 幸福课课程节选

You have to be a happy person because when you're going out,

你得做个快乐的人，因为当你在外面的时候，

纽约的夜晚很开心 - SpeakingMax英语口语达人