Assemble a piece of music by merging the alphabetic representation of the predetermined musical pattern and the provided melodic theme.
X:1
L:1/8
M:4/4
K:G
['dBGB cdBc AGEG D2 B,D', 'bg g2']  
X:1
L:1/8
M:4/4
K:G
 d2 ge dBGB | cdBc AGEG | D2 B,D GABc | dg g2 (3efg ag | bg g2 dBGB | cdBc AGEG | D2 B,D G,B,DG | 
 FGAc BGGB :: dG (3Bcd GBdg | bg g2 dBGB | c3 A BcdB | (3cBA GB ABcd | bg g2 agef | g3 e dBGB | 
 cege dB B2 | cAFA G3 B :|  