Compose a piece of music that follows both the given musical theme and the letter-based structure provided.
X:1
L:1/8
Q:1/4=160
M:2/4
K:G
['c2 BA B2 AG AA GF |1', 'e (=f2 d2) de dc B3 c', 'AG AA GF |1 G4 :|2 G2']  
X:1
L:1/8
Q:1/4=160
M:2/4
K:G
 c2 BA | B2 AG | AA GF |1 G4 :|2 G2 z2 |: GA Bc | d3 e | (=f2 d2) | de dc | B3 c | A2 G2 :| c2 BA | 
 B2 AG | AA GF |1 G4 :|2 G2 z2 ||  