at the end of every other line, he hops between Bm and F#m, listen to the song for the rhythm of it.
intro
G F# Bm F#m x2
G F# Bm F#m
SPOOKY SCARY SKELETONS
G F# Bm F#m
SEND SHIVERS DOWN YOUR SPINE
G F# Bm F#m
SHRIEKING SKULLS WILL SHOCK YOUR SOUL
G F# Bm F#m
SEAL YOUR DOOM TONIGHT
G F# Bm F#m
SPOOKY SCARY SKELETONS
G F# Bm F#m
SPEAK WITH SUCH A SCREECH
G F# Bm F#m
YOU'LL SHAKE AND SHUDDER IN SURPRISE
G F# Bm F#m
WHEN YOU HEAR THESE ZOMBIES SHRIEK
D A
WE'RE SO SORRY SKELETONS
Bm G
YOU'RE SO MISUNDERSTOOD
E C
YOU ONLY WANT TO SOCIALIZE
Db F#
BUT I DON'T THINK WE SHOULD
Rinse and Repeat.