你是我执手天涯的誓言我是你不可消失的永远
[nĭ shì wŏ zhí shŏu tiān yá de shì yán wŏ shì nĭ bù kĕ xiāo shī de yŏng yuăn]
It means 'You are my oath to hold hands and wander across the ends of the earth, I am your eternal presence that cannot disappear.' It expresses profound and unbreakable commitment in a relationship.