The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants.

成功不在于你赚了多少钱，而在于你影响了多少人的生活。

I don’t count my sit-ups, I only start counting when it starts hurting.

The harder you work, the luckier you get.

数学中最重要的是提出正确的问题。