你可以拥有一切，只是你不可能马上拥有一切。

We are all descendants of successful ancestors; failure left no progeny.

How wonderful that we have met with a paradox. Now we have some hope of making progress.

Courage is a virtue necessary not only in war, but in life as well.

数学教会我们逻辑思考并系统地处理问题。