Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
M:4/4
K:C
['F2 G ABc ded cAG', 'g fed cde fed cAG']  
X:1
L:1/8
M:4/4
K:C
[M:6/8][K:D] ee D uce e G[Q:1/8=160]A/G/ | F2 G ABc | ded cAG | FGA cAG | FGA A2 G | F2 G ABc | 
 ded cAG | FDF GAG | FDF G2 :| g | fed cde | fed cAG | FGA cAG | FGA A2 g | fed cde | fed cAG | 
 FDF GAG | FDF G2 :|  