There's a lot to learn in this life. Dance, song, love- these are all things that he thinks he understands. She thinks there is plenty more for him to learn. 

Jimin knows the joy of dancing and of laughing with his friends. He knows the rapture he feels when fans scream his name. He also knows sorrow, and longing, and the pure misery of loving someone who can never, and will never, love you back.