Craft a composition that integrates the assigned alphabet-related musical pattern and the provided melodic theme.
X:1
L:1/8
M:4/4
K:G
['BGGB cAAc', 'dBdg eceg fdef']  
X:1
L:1/8
M:4/4
K:G
 d/c/ | BGGB cAAc | BGGc Bdgd | BGGB cAAc | Bgd^c d3 :| e | dBdg eceg | fdef gage | dBdg eceg | 
 fdef g2 fe | dB TB2 ec Tc2 | dB TB2 AFDd | edef gage | dBcA G3 :|  