Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
M:6/8
K:G
['DB,D GBd e2 d gdB BAB', 'GBd GBd']  
X:1
L:1/8
M:6/8
K:G
 D | GFG DB,D | GBd e2 d | gdB BAB | cBc E2 F | G3 DB,D | GBd e2 d | gdB BAB | cEF G2 :: D | 
 GBd GBd | GBd cBA | GBd efg | fdc def | geg fdf | ede dBG | cBc Adc | BGF G2 :|  