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:G
['GABc dGBd', 'gGGG BGBd', 'BA GdBd GdBd edAB c2']  
X:1
L:1/8
M:4/4
K:G
|: GABc dGBd | edce dcBA | GABc dGBd |1 edAB c2 BA :|2 edAB cdef || gGGG BGBd | gagf edef | 
 gGGG BGBd | cBAB cdef | gGGG BGBd | gagf e2 f2 | geed edcB | cBAB c2 BA |: GdBd GdBd | 
 GdBd c2 BA | GdBd GdBd | edAB c2 BA :|  