I'm a huge Queen fan, though, oddly enough, never took the time to learn any of John's lines (other than the obvious trademark lines of "Another One Bites the Dust" or "Under Pressure") since I'm a singer first and foremost and always focused more on Freddie's parts.
Recently, however, I submitted audition videos for the Queen Extravaganza tour taking place next spring. You had a choice of 4 different songs you could download your specific parts for depending on what you were trying out for (vocals, bass, guitar, drums, etc). The songs were Killer Queen, Somebody to Love, Seven Seas of Rye, and I Want to Break Free. Since I was auditioning for both lead vocals and bass, I chose "Somebody". But you couldn't submit 1 video showing you could do both simultaneously so I sent in two videos. Long story short: they never got there!

I was under the gun trying to get them done hours before the deadline and was faced all week with a ridiculous series of mishaps, notably power outages (due to horrendous snow storms on east coast), flooding, bronchitis, etc. Finally get them uploaded to their site a hour before the deadline and...files ended up being encrypted wrong!

Videos had no sound.
Sigh. It wasn't meant to be, but here's the bass demo at least (now corrected, obviously):
My ill-fated Queen "Somebody to Love" Bass Audition - YouTube
And a live vocal performance + guitar:
Queen - Somebody to Love Live Solo Acoustic - YouTube
The first thing I came to realize about John's lines in "Somebody" are just how deceptively tricky they can be. They initially sound fairly simple but they get progressively busier and more intricate as the song goes on (I NEVER heard that quick run he does right before the line, "He works hard - Everyday - I try and I try - and I try" until I downloaded the bass part!) but it's also the feel that needs to be spot on. I did improvise some parts just to show them I'm not an automatron, LOL. The song's in 12/8, but I may have forced the triplet feel a bit too much or played behind it at times as it's just not as obvious in his playing. But that's why he's John Deacon and I'm not!
Enjoy