等你等到白发苍苍爱你爱到胡子拉碴
[dĕng nĭ dĕng dào bái fā cāng cāng ài nĭ ài dào hú zi lā chá]
Wait until my hair turns white and love you until my chin becomes rough with stubble. This means waiting for you forever and being devoted completely over time regardless of aging.