Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/16
M:2/4
K:A
['E |{G} [AA]2cA (GA).B.c dEBA GBeg |{g}', 'fedc bBba']  
X:1
L:1/16
M:2/4
K:A
 E |{G} [AA]2cA (GA).B.c | dEBA GBeg |{g} a2(ga) .f.e.d.c | dBed [Ec]A[EA] :| g | aAag fedc | 
 bBba gefg | aAag fedc | dfeg aA[FA]g | aAag fedc | bBba gfed | cAdB ecfd | eagb{g} aA!fermata!A ||  