Formulate a musical piece by utilizing the specified motif and alphabet-based structure.
X:1
L:1/4
M:4/4
K:G
['d d']  
X:1
L:1/4
M:4/4
K:G
 G G _B B | G2 =F F | _B B c2 | d2 z d | d d d d | _e2 d d | d d d c | _B2 z2 | d3/2 d/ d c | 
 _B2 G G | _B B c c | d2 z d | d d d d | _e2 d d/d/ | c c _B A | G2 d3/2 d/ | c c A A | G4 |]  