Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
Q:1/8=60
M:3/4
K:G
['cA FA G2-']  
X:1
L:1/8
Q:1/8=60
M:3/4
K:G
"^slow""^simplified version" d/c/ | BG Bc/d/ cA | FA G2- Ge/f/ | g2 eg fd | ec d2- de/f/ | 
 g2 eg fd | Bd e2- eg/e/ | dB GB/d/ cA | FA G2- Ge/f/ | g2 eg fd | Bd e>f g>e | dB GB/d/ cA | 
 FA G2- G2 |]  