Coal is China's main energy source and will remain the cornerstone of China's energy security for a long time to come.

我对那些人们认为不能用于永久结构的脆弱材料感兴趣。

追求科学不仅仅是寻找答案，还要提出正确的问题。

The most important thing is to be honest in your writing.

对你的决定保持承诺，但在你的方法上保持灵活。