Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
Q:3/8=80
M:6/8
K:A
['A>BA BGE ecA BGE e2 e f2', 'c2 B']  
X:1
L:1/8
Q:3/8=80
M:6/8
K:A
|: A>BA BGE | ecA BGE | e2 e f2 e | dcB c2 B | A>BA BGE | ecA BGE | e2 e f2 e | dcB A3 :: 
{d} c2 B ABA | e2 d cdc | a2 e f2 e | edc c2 B | c2 B A>BA | e2 d cdc | a2 e f2 e | dcB A3 :|  