Create a composition by utilizing the given alphabet-based musical pattern and the provided melodic theme.
X:1
L:1/8
M:5/8
K:Bbmin
['g2 f2 e g2', 'B3 Bc d2 c e2 B3']  
X:1
L:1/8
M:5/8
K:Bbmin
 g2 f2 e | g2 f2 e | g2 f2 e | g2 g3 | cd e2 e | e2 e3 | de g2 e | dc B3 :: Bc d2 c | e2 B3 | 
 Bc d2 c | e2 B3 | Bc d2 c | e2 B3 | cB B3 | cB B3 :|  