* Drums: The drums provide a steady beat and help to drive the song forward.
* Bass: The bass provides a low end to the song and helps to fill out the sound.
* Guitar: The guitar adds a light, acoustic sound to the song. It is used sparingly, but it adds a nice touch to the overall arrangement.
* Strings: The strings add a beautiful, ethereal sound to the song. They are used sparingly, but they create a sense of drama and emotion.
* Vocals: Christina Aguilera's vocals are the centerpiece of the song. She sings with incredible power and emotion, and she brings the lyrics to life.