Green years. When they first met, they had similar personalities, so they became best friends. The path of best friends was not easy, they were separated and noisy, but they accompanied each other through elementary school, junior high school, and high school, and they lived in two different places until college: they saw each other from time to time in their freshman year, talked to each other from time to time in their sophomore year, texted from time to time in their junior year, quarreled from time to time in their senior year, and forgot who they were after graduation...