Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:6/8
K:G
['|{GA} B2 D D E G']  
X:1
L:1/8
M:6/8
K:G
 (G/A/) | B3/2 A/ B G3/2 A/ G | B3/2 A/ B G2 (d/c/) | B c A G B d | e3 d2 B/ c/ | d e f g f e | 
 d g B{B} A2 (G/A/) |{GA} B2 D D E G | A3/2 G/ A B3/2 G/ A |{GA} B2 D D E G | A3 G2 |]  