Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/16
Q:1/4=120
M:2/4
K:G
['B2AG F2A2 A2GF', 'g2d2 B2G2', 'agfe dcBA GABc']  
X:1
L:1/16
Q:1/4=120
M:2/4
K:G
 B2G2 B2AG | F2A2 A2GF | G2B2 B2AG | d4 D4 | G2B2 B2AG | F2A2 A2GF | E2G2 A2GF | G4 G,4 :: 
 B2G2 E2G2 | g2d2 B2G2 | B2G2 d2B2 | a4 A4 | B2G2 d2B2 | g2d2 B2G2 | D2G2 A2GF | G4 G,4 :: 
 gfga gbag | agfe dcBA | GABc defg | a4 A4 | gfga gabg | agfe dcBA | GABc d2F2 | G4 G,4 :|  