Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
M:2/4
K:Amin
['AB cB', 'A>B cd eg a2 e2 dB BA']  
X:1
L:1/8
M:2/4
K:Amin
 EA AB | cB AB | FA AB | cB A2 | ^FA AB | cB AB | e2 dB | BA A2 :| A>B cd | eg a2 | e2 dB | BA G2 | 
 A>B cd | eg a2 | e2 dB | BA A2 :|  