Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
M:2/4
K:Ador
['e>g ed', 'ea ab ag']  
X:1
L:1/8
M:2/4
K:Ador
|: e>g ed | ^c/B/A G2 | e>g ed | e/f/g a2 | e>g ed | BA G>A | BG dB | A2 A2 :: ea ab | ag ed | 
 ea ab | ag ef | g>a ge | dB G>A | BG dB | A2 A2 :|  