谷物不仅仅是一种商品，它是文明的基础。

我经历过最寒冷的冬天是旧金山的夏天。

The poor dream all their lives of getting enough to eat and looking like the rich. And what do the rich dream of? Losing weight and looking like the poor.

I don't hold grudges, I remember facts.

感觉是意识的基本事实。

Life was simple before World War II. After that, we had systems.

In the context of computational learning, the concept of 'probably approximately correct' (PAC) learning provides a framework for understanding the efficiency and feasibility of learning algorithms.