Mahabharata 7.50.29

स्मिताभिभाषिणं दान्तं गुरुवाक्यकरं सदाबाल्येऽप्यबालकर्माणं प्रियवाक्यममत्सरम्

smitābhibhāṣiṇaṃ dāntaṃ guruvākyakaraṃ sadābālye'pyabālakarmāṇaṃ priyavākyamamatsaram

Our plain-language meaning of this verse is waiting for scholar review.