Develop a musical piece employing the provided motif and an alphabet-based structure.
X:1
L:1/4
Q:1/2=100
M:2/2
K:G
['A3/2 B/ A d', 'f d2']  
X:1
L:1/4
Q:1/2=100
M:2/2
K:G
|: d/c/ | B G2 d/c/ | B G2 d | g2 f e | d G2 G | A3/2 B/ A d | A3/2 B/ A d | E F G A | F D2 :: 
 a/g/ | f d2 a/g/ | f d2 d | e f g a | f d2 d | e g c e | d g B e | d c B A | B G2 :|  