Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/4
M:4/4
K:C
['G3/2 F/ E F']  
X:1
L:1/4
M:4/4
K:C
"C" G3/2 F/ E F |"C" G3/2 F/ E F |"C" G A"G7" F D |"C" C3 z :|"Am" c3/2 B/ A B |"Am" A2 E2 | 
"Dm" F3/2 E/"G7" D A |"C" G"F7" F"C" E G |"F" c3/2 B/ A B |"Dm7" c B c A |"C/G" G A"G7" F D | 
"C" C3 z |]  