刻骨铭心说爱你沧海桑田说爱我
[kè gú míng xīn shuō ài nĭ cāng hăi sāng tián shuō ài wŏ]
This expresses eternal love through phrases. '刻骨铭心说爱你' means loving deeply and unforgettable love, while '沧海桑田说爱我' implies saying ‘love me’ amidst changes of time, showing undying and constant love over time.