做你自己，其他角色都已经有人扮演了。
We can’t ignore the economic role of coal, but we also can’t ignore its environmental impact.
The only way to learn mathematics is to do mathematics.
When you get an invitation to do something in the future， ask yourself: would you accept this if it was scheduled for tomorrow？ Not too many promises will pass that immediacy filter.
Most of us spend too much time on what is urgent and not enough time on what is important.