Coal is China's main energy source and will remain the cornerstone of China's energy security for a long time to come.
Every patient’s story is a lesson in medicine.
真相很少纯粹，也绝不简单。
The less I know about other people's affairs, the happier I am.
It's easier to ask forgiveness than it is to get permission.
解释：不注意天时，财富就不能增长；不注意地利，粮食就不会充足。
We shall be everything to each other. Nothing else shall be of any consequence.