扯痛嘴角也不知該如何
[chĕ tòng zuĭ jiăo yĕ bù zhī gāi rú hé]
This translates into something like 'even hurting the corner of my mouth (forcing smile), not knowing how to deal with it', showing emotional pain concealed behind pretended cheerfulness, uncertainty facing life’s situations, or unspoken feelings kept inside because they cannot be easily articulated.