忘你在笑凝固嘴角后想你在泪滑落面颊前
[wàng nĭ zài xiào níng gù zuĭ jiăo hòu xiăng nĭ zài lèi huá luò miàn jiá qián]
Translating to 'forgetting you when smiling becomes frozen on the lips; thinking of you before tears slide down the cheeks,' it portrays the bittersweet struggle between joy and sadness, emphasizing moments when happiness turns to sorrow due to missing someone deeply.