青春不是年华，而是心境；青春不是桃面、丹唇、柔膝，而是深沉的意志，恢宏的想象，炙热的恋情；青春是生命的深泉在涌流。
Youth is not a time of life; it is a state of mind; it is not a matter of rosy cheeks, red lips and supple knees; it is a matter of the will, a quality of the imagination, a vigor of the emotions; it is the freshness of the deep springs of life.
解释：把腹心的疾病去掉，而放在大腿胳臂上，有什么益处？
"In computer science, we are always trying to find the balance between expressiveness and tractability."
I want to create a world where everything is connected.
"Deep learning is a form of machine learning that enables computers to learn from experience and understand the world in terms of a hierarchy of concepts."