Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:4/4
K:C
['[EC] [GE]3']  
X:1
L:1/8
M:4/4
K:C
"C" [EC]>[EC] [EC][FD] [GE]2 [EC]2 |"G7" [FB,]>[FB,] [FB,][cA] [BG]3 z | 
"G7" [DB,]>[DB,] [DB,][EC] [FD]2 [FD][GE] | [BG]>[AF] [GE][FB,]"C" [EC]3 z | 
"F" [AF]2 [BG][cA] [BG]2 [AF]2 |"C" [AF]2 [GE]2 [BG]3 [AF] |"G7" [GE]2 [FD]2 [AF]3 [GE] | 
"C" [FD]2 [EC]2 [GE]3 [EC] |"G7" [GE]3 [FD] [FD]2 [dF]2 |"C" [cE]4 [EC]3 [EC] | 
"G7" [GE]3 [FB,] [FB,]2 [B,G,]2 |"C" [CE,]6 z2 |]  