I don’t think you can compare different eras. Every era has its own challenges and its own special things.

Sustainability isn't an option anymore—it's a necessity for any responsible mining operation.

The most sustainable aquaculture operations are those that mimic nature.

Dance like nobody's watching, love like you've never been hurt.

语言是一种人类自发的创造，语言的发展遵循一定的规律。在人生的某一时期它会达到某种程度。