The only way to get to the top of the ladder is to climb it step by step.
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。
Sustainability isn't a trend; it's the future of food production.