经济与生态之间的平衡是现代林业的核心。

技术必须同时服务于行业和环境，别无他法。

The pharmaceutical industry must balance profit with purpose—our mission is to heal, not just to sell.

But what is happiness except the simple harmony between a man and the life he leads?

解释：齐国是强国，利用它的强大进攻宋国，让他逞强，燕国就可以乘机打败齐国；齐国是大国，利用它的大国野心吞并宋国，增加土地，燕国就可以乘机进攻。