死者比生者更忠实。他们不会改变。

The only limit to our realization of tomorrow is our doubts of today.

I’m not a guy that’s going to let my family down.

So long as you have food in your mouth, you have solved all questions for the time being.

可能近似正确（PAC）学习的概念在计算学习理论中具有基础性意义。