The task of psychology is to reduce complex mental phenomena to their simplest components.

家庭是一个生产和消费商品与服务的小工厂。

The American farmer is the only man in our economy who has to buy everything he buys at retail, sell everything he sells at wholesale, and pay the freight both ways.

可持续性不仅仅是一个流行词，更是我们对后代的责任。