It's not a sign of meekness To say you're wrong, When you discover your mistake. It doesn't show your weakness, It shows you're strong, When you admit a blunder that you make. For, I know now, You're the only one, I know now, I'm the lonely one, I had to learn how a heart can yearn, How tears can burn, With no one to turn to. I know now, That I can't forget, I can't, for I don't know how, I guess I never knew How I needed you, But sweetheart, I know now. I know now, That I can't forget, I can't, for I don't know how, I guess I never knew How I needed you, But sweetheart, I know now. source: www.lyricsondemand.com/soundtracks/0/42ndstreetlyrics/iknownowlyrics.html

Beautifully done. I think that melody is harder to sing than it sounds.