Compose a musical piece using the designated musical pattern's alphabetic representation and the assigned melodic theme.
X:1
L:1/8
M:4/4
K:G
['', 'BG G2 DGGD', 'gage fd d2']  
X:1
L:1/8
M:4/4
K:G
 d |: BG G2 DGGD | Bdef gedc | BG G2 DGGD | ABAG EG D2 :| gage abaf | gage fd d2 | gage a2 ga | 
 b3 a gfed | g3 e a3 f | gage fd d2 | g3 e a2 ga | b2 ba gfed ||  