可持续性不是一种选择，而是一种责任。
The best way to learn mathematics is to do mathematics.
Mental processes exist because they have served life's continuance.
Success is going from failure to failure without loss of enthusiasm.
I was messed up for a long time.
什么是成功？我认为这是对你所做的事情有一种天赋的混合；知道这还不够，你必须努力工作并有一定的目标感。