And just like that jolly laugh you cannot resist joining in, a smile can be contagious and you as the spreader become instrumental in not only your own happiness but that of others as well.

就像你无法抗拒开心的微笑一样，微笑是会传染的，你也可以成为微笑的传播者，在帮助自己开心起来的同时也带给别人快乐。