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
['G2 G B/c/dB GBG B2 A GBG', 'A G2 G GB/c/d/B/ GAB gdB cAc', 'g3 def', 'BGG ADD', 'gdB gdB']  
X:1
L:1/8
M:6/8
K:G
 G2 G B/c/dB | GBG B2 A | GBG GB/c/d/B/ | AFA c2 A :: G2 G GB/c/d/B/ | GAB gdB | cAc BgB | 
 AFA c2 A :| g3 def | gfe dBG | g3 def | AFA c2 A | g3 def | gfe dcB | cAc BgB | AFA c2 B || 
 BGG ADD | BGG ABc | BGG ADD | AFA ABc | BGG ADD | GAB gdB | cac BgB | AFA c2 A || gdB gdB | 
 GAB d2 B | gdB gdB | AFA c2 A | gdB gdB | GAB gdB | cAc BgB | AFA c2 A ||  