你就是一首我唱不完的歌
[nĭ jiù shì yī shŏu wŏ chàng bù wán de gē]
A poetic expression equating a loved one to an unfinished song that can never be sung entirely conveys feelings towards someone that seem inexhaustible like endless tunes. Here it refers to deep affection and appreciation of the person, whose charm can be discovered eternally and boundlessly, similar meanings like saying the person brings inspiration continually just like beautiful music.