The past, like the future, is indefinite and exists only as a spectrum of possibilities.
农业效率绝不能以生物多样性为代价。
Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.
数学不是关于数字、方程、计算或算法的:它是关于理解的。
Sustainability isn't just a trend; it's the future of leather tanning.