Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
M:4/4
K:G
['d2 dg edcB dgfg edcB', 'G2 Bc d2 de dBGB c2 e2']  
X:1
L:1/8
M:4/4
K:G
 Bc | d2 dg edcB | dgfg edcB | DGBG DGBG | DGBd cBAG | d2 dg edcB | dgfg edcB | g>abg ecAF | 
 G2 G2 G2 :| Bc | d2 de dBGB | c2 e2 e2 z2 | cBcd cAFD | dgfa g2 g2 | dBdg eceg | fdfa gfga | 
 bgbg ecAF | G2 G2 G2 :|  