一个只能被儿童欣赏的儿童故事根本不是一个好的儿童故事。
Sustainability isn't a destination—it's a daily practice.
以物易物、互通有无的倾向是人类共有的,也是其他动物所没有的。
The major credit I think Jim and I deserve... is for selecting the right problem and sticking to it.