Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:4/4
K:G
['G2 BG G2 Bd cBAB cdeg edcB', 'g2 bg ef/g/ dg']  
X:1
L:1/8
M:4/4
K:G
 G2 BG G2 Bd | cBAB cdeg | edcB cdeg | ecAF GFED | G2 BG G2 Bd | cBAB cdeg | edcB cdeg | ecAF G4 || 
 g2 bg ef/g/ dg | egdg egdg | g2 bg ef/g/ dg | egfa gg/g/ g2 | g2 bg ef/g/ dg | egdg egdg | 
 bgaf gfed | edef gedB ||  