Craft a piece of music that integrates both the suggested theme and letter-based structure.
X:1
L:1/4
M:4/4
K:C
['G F']  
X:1
L:1/4
M:4/4
K:C
 z3 G | G3/2 G/ G G | F E F G | c/c/ G G F | G3 z | G2 G G/G/ | F E F G | c G F E | C3 z |]  