你非我良人怎知我情深你非我伊人怎知我痴情
[nĭ fēi wŏ liáng rén zĕn zhī wŏ qíng shēn nĭ fēi wŏ yī rén zĕn zhī wŏ chī qíng]
It expresses deep feelings for someone, implying that unless you are the right one for me, you wouldn't understand how deep my love and devotion can be. The phrase has a tone of melancholy longing.