 " We Belong Together " is a simple , understated musical arrangement set in F lydian and composed in 4 / 4 time . Similarly , within the song , Carey 's voice spans from G3 to the high note of A5 . Carey 's vocal range is demonstrated with a greater emphasis in the ending chorus , where the chorus is raised an octave higher , lying from G4 to A5 . As such , Carey ends with an anticipated coda , completing both the chorus and the song with a potent , belted note of C5 for approximately four semibreves ( around 17 seconds ) . It follows the common verse @-@ chorus form and is structured into three sections that portray the protagonist in a range of emotions ; from doleful and resigned in the first section , to desperate and agitated in the second . In the last section the song climaxes with an octave raise , which not only emphasizes the protagonist 's heightened desperation , but her determination to be with her lover . The song is written in the key of C major with a slow tempo of 70 beats per minute . Carey 's vocals span from G3 to A5 , and the song follows a chord progression of Am – G – Em – F. 
