你必须花费一些精力和努力才能看到数学的美。
You have to spend some energy and effort to see the beauty of math.
Don’t create things to make money； make money so you can create things. The reward for good work is more work.
PID控制器是控制工程师的通用工具，适用于各种各样的过程。
You have to be willing to fail, to be wrong, to look foolish.
No matter what happens in life, be good to people. Being good to people is a wonderful legacy to leave behind.
我喜欢在股票打折时买入。