When I got my long-overdue graduation certificate, my longing for lost love became stronger. One year after graduation, I barely passed a make-up exam for a homework, and received a graduation certificate from the head of the department, on which was a photo of me when I graduated. This is a one-inch black and white photo without a hat. On the photo paper, there is an incomprehensible expression in the eyes.Thinking of my graduation photos from the other two periods, I can't help but feel like things have changed. In the primary school graduation photo, my immature face showed an innocent and innocent smirk from the heart; in the middle school graduation photo, I grinned open my mouth covered with black fluff, forcing a fake smile on my face; And this picture, no matter how hard I try, I can't laugh.