The soul is healed by being with children.
The secret to success is learning how to use pain and pleasure instead of having pain and pleasure use you. If you do that, you’re in control of your life. If you don’t, life controls you.
解释：货卖完了才知道不足，是由于不懂得计量；事情结束了才知道有余，是由于不懂得调节。
The future of drones belongs to those who dare to dream and take action.