Craft a musical composition that incorporates the supplied alphabet sequence and motif.
X:1
L:1/8
M:12/8
K:G
['B2 A', 'B2 A']  
X:1
L:1/8
M:12/8
K:G
 d2 g B2 A G2 B AGA | B2 A ABd e2 d B2 c | d2 g B2 A G2 B AGA | B2 A B2 A G3 G3 :| 
 B2 A ABd e2 d B2 A | B2 A ABd e2 d B2 c | d2 g B2 A G2 B AGA | B2 A B2 A G3 G3 :|  