Paul McCartney’s song “Yesterday” deserves some analysis, as it is very decently written. The song has a tight motivic unity. Notice how the first word “Yesterday” has the rhythm short/short/long, which is then reversed on the words “far away” at the end of the phrase (the rhythm becomes long/short/short). This retrograde form of the rhythm gets repeated two more times, the last time on the word “yesterday” at the end of the A section, thus bringing things full circle.
The harmony is interesting, too. McCartney starts on the simple strummed C major triad which gives the piece an almost folk-like simplicity. However, he quickly shifts to a II-V-I progression (Bmin7/E7/Amin) which is a classic jazz progression (his father was a jazz pianist), but quickly moves away from it back to the more folksy triads. Chords in jazz songs rarely sink below the level of seventh chords; triads are very unusual. Also, at the end of each section is a plagal cadence (IV-I), also known as the “Amen cadence,” because all hymns used to end that way with those two chords on the word “A-men.” This gives the song an almost religious solemnity.
This is done very subliminally and seamlessly. There is nothing forced or awkward about the integration of these three different harmonic techniques. This is true composition – a “putting together” (com-posere) into a seamless whole.
Oh, and ignore the occasionally screaming girls on the recording. The song is much better than they could possibly realize!