Craft a musical composition that adheres to the specified musical theme and letter-based structure.
X:1
L:1/8
M:2/4
K:C
['Gc ce d/c/d/e/ Ac Bc c/d/e/f/ geeg', "z e/f/ geae gee e/f/ ge c'e"]  
X:1
L:1/8
M:2/4
K:C
 Gc ce | d/c/d/e/ Ac | Bc c/d/e/f/ | geeg | a>b a/g/f/e/ | f/e/d/c/ Ac | Gc c/B/c/d/ | ecc z :: 
 e/f/ | geae | gee e/f/ | ge c'e | g/a/g/e/ gg | a>b a/g/f/e/ | f/e/d/c/ Ac | Gc c/B/c/d/ | ecc :|  