Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:2/4
K:E
['B, EFGA B2 B2 cc/c/cc BBBA G2']  
X:1
L:1/8
M:2/4
K:E
 B, | EFGA | B2 B2 | cc/c/cc | BBBA | G2 F2 | E2 z2 | E>FGA | Bc/B/B z | e2 f/e/d/c/ | B2 z G | 
 A>AAB/A/ | G2 GG | AAAB/A/ | G2 G2 | AAAB/A/ | GGG z | B>BBB | G2 z |]  