Editing Song structure (section)

==AABA form==
{{Unreferenced section|date=February 2020}} 
{{Main article|Thirty-two-bar form}}
Thirty-two-bar form uses four sections, most often eight measures long each (4×8=32), two verses or A sections, a contrasting B section (the bridge or "middle-eight") and a return of the verse in one last A section (AABA). The B section  is often intended as a contrast to the A sections that precede and follow it. The B section may be made to contrast by putting it in a new harmony. For example, with the [[jazz standard]] "[[I Got Rhythm]]", the A sections are all tonic prolongations based around the I–vi–ii–V [[chord progression]] (B{{music|flat}} in the standard key); however, the B section changes key and moves to V/vi, or D<sup>7</sup> in the standard key, which then does a [[circle of fifths]] movement to G<sup>7</sup>, C<sup>7</sup> and finally F<sup>7</sup>, setting the listener up for a return to the tonic Bb in the final A section.

The "I Got Rhythm" example also provides contrast because the harmonic rhythm changes in the B section. Whereas the A sections contain a vibrant, exciting feel of two chord changes per bar (e.g., the first two bars are often B{{music|flat}}–g minor/c minor–F<sup>7</sup>), the B section consists of two bars of D<sup>7</sup>, two bars of G<sup>7</sup>, two bars of C<sup>7</sup> and two bars of F<sup>7</sup>. In some songs, the "feel" also changes in the B section. For example, the A sections may be in swing feel, and the B section may be in Latin or Afro-Cuban feel.

While the form is often described as AABA, this does not mean that the A sections are all exactly the same. The first A section ends by going back to the next A section, and the second A section ends and transitions into the B section. As such, at the minimum, the composer or arranger often modifies the harmony of the end of the different A sections to guide the listener through the key changes. As well, the composer or arranger may re-harmonize the melody on one or more of the A sections, to provide variety. Note that with a reharmonization, the melody does not usually change; only the chords played by the [[accompaniment]] musicians change.

Examples include "[[Deck the Halls]]":
:A: Deck the hall with boughs of holly,
:A: 'Tis the season to be jolly.
:B: Don we now our gay apparel,
:A: Troll the ancient Yuletide carol.