Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
M:3/4
K:Amix
['fg a4 ba f2 A3 d e4']  
X:1
L:1/8
M:3/4
K:Amix
 Bd | e4 fa | f4 ed | B2 A2 GB | A4 fg | a4 ba | f2 A3 d | e4 de | f4 fg | a4 ba | f2 A3 d | 
 e4 de | f4 fe | d3 efa | f4 ed | B2 A2 GB | A4 |]  