Peace is not free, it requires constant effort to maintain.
和平不是免费的,需要不断努力维护。
"The unexamined life is not worth living."
The hardest single part of building a software system is deciding precisely what to build.
数据驱动的政策对于确保海洋资源的长期可持续性至关重要。
能源革命的核心是清洁高效,煤炭行业必须主动适应这一趋势。