嘴在倔强心在投降
[zuĭ zài jué qiáng xīn zài tóu jiàng]
'zuǐ zài juéjiàng xīn zài tóuxiáng', translated as 'mouth in stubborness heart surrenders'. It vividly portrays internal emotional conflict - on surface (or lips) remains strong-willed while internally yields, possibly due to deep love or unspoken understanding.