Many years later, at the joint liberal arts and sciences reunion of No. 1 Middle School in City A, after three drinks, we talked about the stories between boys and girls in those years, stories about youthful regrets. Ji Cheng, who was sitting in the corner, lost in thought, raised his hand to send a proposition to Mr. Yan, who was studying in graduate school on the other side of the ocean, "Proof: True love is not called youthful frivolity." In the middle of the night, a message from Mr. Yan came on the mobile phone and replied: "I agree." Ji Cheng rubbed his eyes to dissipate sleepiness and regained his energy, "Science student, I want you to demonstrate! Where is the argument?" The next second, the call rang, and on the other end of the phone, Mr. Yan chuckled and said, "We are." Her lover owed her a passionate youthful love, but promised her a long-term reunion. Regarding the proposition of love, as long as our story is used as an argument, everything makes sense. Ji Cheng smiled sweetly, said "Oh" and said good night, have a good night's sleep.