那个菇凉曾笑靥如花那个先森曾被你遗忘
[nèi gè gū liáng céng xiào yè rú huā nèi gè xiān sēn céng bèi nĭ yí wàng]
It translates to: That girl once smiled like a flower but that Mr. was once forgotten by you. It carries a tone of reflection on a bittersweet past experience or nostalgia.