Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/4
M:4/4
K:C
['G G']  
X:1
L:1/4
M:4/4
K:C
 G | G G G G | G e c B | A A A/A/ A | A f d c | B B d/c/ d | e2 f/e/ d | c c d/c/ d | c2 z |]  