Craft a musical composition that incorporates the supplied alphabet sequence and motif.
X:1
L:1/8
M:2/4
K:G
['B2 d/c/B/A/ B2']  
X:1
L:1/8
M:2/4
K:G
 D | GGGA | BAGG | B2 d/c/B/A/ | B2 GG/B/ | dddd | edcB | ABcc | dcBA | B2 d/c/B/A/ | B2 G |]  