Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:3/4
K:G
['Gd e2 e2']  
X:1
L:1/8
M:3/4
K:G
 g3 deA | Bd f2 a2 | g3 dec | BG A4 | Gd e2 e2 | ee =f2 d2 | Gd e2 e2 | BG A4 |]  