5cm per second is a realistic animation created by Makoto Shinkai, which was officially released in Japan on March 3rd, 2007. Animation takes a teenager as the story axis and develops three consecutive animated short stories. The time background is from 1990 to modern Japan, and the changes in Tokyo and other regions are shown through the life of teenagers. The first sentence of Sakura Copy describes the love between Gui Shu and Li Ming when they were young, and the day of reunion. In the second sentence, the astronauts described the lives of Keisuke and Li Ming from the perspective of Miao Hua Akita, who was fond of Keisuke who entered high school. The third sentence, at a speed of 5 cm per second, depicts the inner feelings of Gui Shu and Li Ming when they grow up. I missed the opportunity to express my mind at that time. This is a lifelong regret, but it is also a kind of regret. I remember that youthful love in the memory time!