Construct a musical work that combines the specified alphabet-based pattern with the given melodic theme.
X:1
L:1/8
M:2/2
K:G
['[GB]3 [GB] [GB]2', '[GB]3 [GB] [GB]2']  
X:1
L:1/8
M:2/2
K:G
 gaga f3 g | e2 d2 dcBB | b2 ab agfg | a2 ga gdef | g2 ag fgfd | e2 d4 AB | cBcd cAFA |1 
 [GB]3 [GB] [GB]2 ef :|2 [GB]3 [GB] [GB]2 (G,2 |: G,)B, D2 B3 d | e2 d2 dcBd | cBAG FGAc | 
 BAGB AGEG | DB, D2 B3 d | e2 d4 AB | c2 cd cA F2 |1 [GB]3 [GB] [GB]2 G,2 :|2 
 [GB]3 [GB] [GB]2 ef ||  