Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:3/4
K:G
['GBd ec A']  
X:1
L:1/8
M:3/4
K:G
 GBd ec A | GBd e c2 | GBd ec A | BGG E c2 | A2 A2 FD | GGG B c2 | A2 AG FD | GBc A G2 |]  