Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:2/2
K:F
['CFFG A>GFA DGGA B>ABc dfcA GFGA C<FE>G', 'F2 f<cc>A fcfa fcfa gfga fdcA dbag']  
X:1
L:1/8
M:2/2
K:F
|: CFFG A>GFA | DGGA B>ABc | dfcA GFGA | C<FE>G F2 F2 :: f<cc>A fcfa | fcfa gfga | fdcA dbag | 
 f<dc>A G2 G2 :|  