Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/8
M:6/8
K:G
['gfg dcB', 'a2 b']  
X:1
L:1/8
M:6/8
K:G
 A/B/ | cAA EAA | cBA edc | BGG dGG | gfg dcB | cAA eAA | cBA e2 f | gfg dcB | cAA A2 :| d | 
 efg a2 b | a2 b agf | efg a2 b | agf g2 d | efg a2 b | a2 b agf | gfg dcB | cAA A2 :|  