The Beatles US breakthrough single, is a good, rather than a great, song. It feels too much like conscious attempt at a greatest hits of tricks and techniques.
Intro - culled from another part of the song (the guitar chords from the end of the bridge). Just like She Loves You , Please Please Me & From Me To You .
End – triplets from Twist & Shout.
Bridge – a key change (from G to C) into a stock jazz chord progression uses exactly the same jump (up a fourth) and exactly the same first 3 chords (ii, V, I) as From Me To You .
Words - are kept to a minimum (only 36 words in the whole song) and we get the title once in every verse, twice in the choruses and 3 times in the last chorus.
We get the lyrical echos
I’ll tell you something/When I say that something/you got that something/ When I feel that something
I feel happy/ It’s such a feeling
Three Cheers For B7
When they’re not going over old ground, it’s pretty uninspiring.
The chorus is an unimaginative straight doo wop progression
IV, V, I, vi.
IV, V, I
C D G Em
C D G
The vocal melody is pretty stepwise and not very compelling apart from the nice touch in the verse of moving from a B down to a low F# on the 2nd line (I think you'll underSTAND) and from B up to a high F# on the 4th (I want to hold your HAND).
The most interesting thing is the B7 in the verse
I, V, vi, III7
G D Em B7
Other than that there isn’t anything here that the Beatles haven’t used to better effect in other songs.
But maybe what they needed to break America (other than some illegal bootlegging) was a kind of sample platter of the Mersey sound. In which case this song is a work of genius.