Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
Q:3/8=120
M:6/8
K:C
['cBc G3 c2 c d2', 'G2 G E2 C']  
X:1
L:1/8
Q:3/8=120
M:6/8
K:C
 g | e2 c A2 d | cBc G3 | c2 c d2 e | f2 e d2 g | e2 c A3 |{d} cBc G3 | c2 c d2 f | efd [cC]3 :: 
 G2 G E2 C | G2 G E2 C | c2 c d2 e | f2 e d3 | G2 G E2 C | G2 G E2 C | cBc d2 f | efd [cC]3 :|  