Tīng wán mǔqīn de fèi fǔ zhī yán, tā bùjīn liú xià le yǎnlèi.
Listening to his mother's heartfelt words, he couldn't help but shed tears.
Tips
history
From Bai Juyi's (白居易) Tang-dynasty poem 《代书诗一百韵寄微之》: '肺腑都无隔,形骸两不羁' — 'between our hearts there is no barrier.' 肺腑 (lungs and organs) stood for the innermost self.
culture
In traditional Chinese medicine and rhetoric, 肺腑 — the internal organs — represent the deepest, most private self (like 'from the bottom of my heart' in English). Used when stressing sincerity, often paired with 推心置腹.