To understand behavior, look for the utility in it.

贫家如果要仿效富家的穿衣吃饭及庞大的花费，那就一定会很快招致灭亡。 

书是一次心灵的旅程。

过去从未消逝，它甚至还未成为过去。

Sustainability isn't just a buzzword; it's our responsibility to future generations.

我对这场战争了解的不多，但我知道美国的很多年轻人都参与了这场战争。