Create a composition by utilizing the given alphabet-based musical pattern and the provided melodic theme.
X:1
L:1/4
M:2/4
K:G
['d G', 'd g']  
X:1
L:1/4
M:2/4
K:G
|: B/c/ | d G | B A/G/ | d G | g e | d G | d c/B/ | c A | A B/c/ | d G | B A/G/ | d G | g3/2 B/ | 
 c A | d/e/d/c/ | B G | G :: B/c/ | d g | B g | d g | G A/B/ | c f | A f | c f | A B/c/ | d g | 
 B g | d g | G A/B/ | c A | d/e/d/c/ | B G | G :|  