Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
Q:1/4=120
M:6/8
K:G
['c>Bc/B/ AFD B>AG FAF DFA']  
X:1
L:1/8
Q:1/4=120
M:6/8
K:G
 G2 d BGE | c>Bc/B/ AFD | B>AG FAF | DFA G2 c- | c z/ B/c/d/ ecA | B>AB/c/ dBG | c>Bc ecA | 
 Bce d2 g- | g z/ f/e dBG | c>Bc/B/ AFD | B>AG FAF | DFA G2 |]  