你若有情我必有心
[nĭ ruò yŏu qíng wŏ bì yŏu xīn]
'If You Are Sentimental, Then I Shall Be Heartfelt.' Indicating a reciprocal attitude in emotions: when encountering someone with true intentionality towards themself, they also open up with all sincerity, expressing mutual response and harmony in affections or sentiments.