Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/8
M:2/4
K:G
['bb/a/ gd ee/d/ c2', 'dB de dc c/B/c af']  
X:1
L:1/8
M:2/4
K:G
 bb/a/ gd | ee/d/ c2 | ee/d/ ce | dd/c/ Bd | bb/a/ gd | ee/d/ c2 | ef/e/ df/a/ | gg g2 :: dB de | 
 dc c/B/c | af ab | ag g/f/g | dB de | dc c/B/c | af ab/a/ | gg g2 :|  