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
['[BG]2 [BG]D']  
X:1
L:1/8
M:4/4
K:G
 D2 |"G" [BG]2 [BG]D [BG]2 [BG]D |[M:3/4] [BG]2 [BG][AF] [BG][cA] |"D7" [AF]4 [AF][BG] | 
[M:4/4] [cA]2 [cA]D [cA]2 [cA]D |[M:3/4] [cA]2 [cA][BG] [cA][dB] |"G" [BG]4 :: [dB]2 | 
[M:4/4]"C" [ec]2 [dB]2 [cG]4 |"G" [dB]2 [cA]2 [BG]4 |[M:3/4]"D7" [AF]3 [BG] [cA]2 |1 
"G" [BG][AF] [BG][cA] :|2"G" [BG]4 |]  