只管走过去，不必逗留着采了花朵来保存，因为一路上花朵自会继续开放的。
Do not linger to gather flowers to keep them,but walk on,for flowers will keep themselves blooming all your way.
The PAC learning framework provides a formal way to quantify the learnability of a concept class.
人生中最辉煌的时刻不是那些所谓成功的日子，而是你从沮丧和绝望中向生活发起挑战并承诺未来成就的日子。
未经审视的生活不值得过。
