Develop a musical composition that includes the supplied motif while following the designated alphabetical pattern.
X:1
L:1/8
M:2/4
K:G
['B2 A2']  
X:1
L:1/8
M:2/4
K:G
 GDGA | B2 A2 | G4 | dcBc | d2 ed | cBAB | c2 dc | BAGD | B2 A2 | G4 |]  