Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:6/8
K:Ador
['e>AA e>AA', 'e>aa e>aa']  
X:1
L:1/8
M:6/8
K:Ador
 e>AA e>AA | B>GG B>GG | e>AA e>AA | def gdB | e>AA e>AA | B>GG B>GG | def gdB | BAA A3 :| 
 e>aa e>aa | e>gg e>gg | e>aa e>aa | def gdB | e>aa e>aa | e>gg e>gg | def gdB | BAA A3 :|  