Madonna's vocal range spans almost one octave from F3 to D4. As she begins to sing the first verse, the bass pedal changes to C major, changes back to F during the chorus, and back to D minor during the chorus closure. This process is repeated during the second verse and chorus, which abruptly ends in a silence, with only the low and lifeless sound of the synthesizer, set in D minor. Madonna then starts to sing the bridge (or middle part)—"If I ran away, I'd never have the strength"—between the tonal keys of D and F, closing with the repetition of the chorus until the song gradually fades out. The original composition of the song did not have the background synths, instead Leonard created a basic structure on piano, and Madonna added the words on top of it. According to Leonard, Madonna came up with the bridge by herself, extending it from the music that he was playing.