Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:4/4
K:C
['e2 ec A2 Ac']  
X:1
L:1/8
M:4/4
K:C
|:"Am" e2 ec A2 Ac |"G" Bd gf e2 d2 |"F" e2 ec A2 Ac |"G" BA GB A4 ::"F" AG FG AB cA | 
"G" Bd gf e2 c2 |"F" AG FG AB cA |"Am" B2 G2 A4 :|  