Develop a musical piece employing the provided motif and an alphabet-based structure.
X:1
L:1/8
M:6/8
K:Dmix
['', 'AFD D2 c', 'c BGB', 'c BGB', 'c BGB def gfe dcB AFD']  
X:1
L:1/8
M:6/8
K:Dmix
"^A" |: c | BAB G2 F | E2 F G2 c | BAB |1,3 G2 B | AFD D2 c :|2,4 dcB | AFD D2 :|"^B" |: c | 
 BGB d2 c | BGB d2 c | BGB dcB | AFD D2 || | c | BGB d2 c | BGB def | gfe dcB | AFD D2 :|  