你蓝瞳深似海她青瞳浅若溪
[nĭ lán tóng shēn sì hăi tā qīng tóng qiăn ruò xī]
Your blue eyes are as deep as the ocean; her green eyes are as shallow as a stream. It uses metaphor of different eye colors to depict unique features of two individuals in comparison, implying depth or simplicity of their characters.