我笑的那么欢扯痛了嘴角
[wŏ xiào de nèi me huān chĕ tòng le zuĭ jiăo]
'I Smile So Cheerfully That It Hurts at the Corners of My Mouth' captures an ironic state where one's facial expression (a broad smile) contrasts with genuine inner turmoil or pain, often associated with forced smiles to mask sadness.