Perfect to start the process if you are a fan of this unique duet and the result of their collaboration. I just love how the talents of Shakira combined with that of Beyonce and gave this song so much power (Columbian and Afro-American)! The arrangement teaches how to understand the way the vocal part works with piano accompaniment, which is a good practice for both singers and instrumentalists. It's a vocally complicated composition but very rewarding in the end.