On the bus, they met by chance.
"Xu Yannian, pretend you don't know me?"
On that autumn night, they watched the stars and the moon together.
"Jiang Jiayu, let's get admitted to Peking University together and go to Beicheng to watch the snow."
On a rainy night, they parted.
"Xu Yannian, that's it. What I mean is, we're done here."
They met again on the trails of Peking University.
Xu: "Classmate, I'm sorry, but I can borrow it for a moment."
On the last winter night, they talked through the screen.
"Xu Yannian, your promise is almost overdue. Come back, please. I won't force you to leave..."
Intention: Don't wait until he/she is gone to cherish him/her.