The song is in the key of A major. After an introduction in D chord on the guitar the verse begins in A (I) on "When I see you I just don't know what to say" ending that line with E (V). The verse also features a D (IV) chord. Musicologist Dominic Pedler cites the song as an example of how "one of The Beatles' greatest contributions to pop songwriting was their skill in combining the familiarity of simple I-IV-V sequences with dramatically new harmonic material". The bridge features an "8-7-flat7-6" glide in consecutive semitones down the chromatic scale, a device subsequently used by the Beatles in "Michelle", "Cry Baby Cry", "Got to Get You into My Life", "And Your Bird Can Sing" and "Mother Nature's Son".Dominic Pedler. Songwriting Secrets of the Beatles. Omnibus Press. 2003. pp311-314
