Formulate a musical piece by utilizing the specified motif and alphabet-based structure.
X:1
L:1/8
M:2/2
K:G
['GBAG FDCE DGGF GABc', 'gfga gd (3ddd gdad gdde', 'GBAG FDCE DGGF GABc', '(3ddd gdad gdde']  
X:1
L:1/8
M:2/2
K:G
 BAGB AF D2 | GBAG FDCE | DGGF GABc | d^cde fd=cA | B2 GB AF D2 | GBAG FDCE | DGGF GABc | 
 dBcA BGGA | BG (3GGG AF (3FFF | GBAG FDCE | DGGF GABc | d^cde fd=cA | B2 GB AF D2 | GBAG FDCE | 
 DGGF GABc | (3dcB cA BG G2 |: gfga gd (3ddd | gdad gdde | =fefg fc (3ccc | ^fgag fdcA | 
 gfga gd (3ddd | gdad gdde | =f4 g4 | a2 ag ^fdcA ::"^variations" BdcB AcBA | GBAG FDCE | 
 DGGF GABc | d^cde fd=cA | B2 GB AFDF | GBAG FDCE | DGGF GABc | dBcA BGGA :: gfga gd (3ddd | 
 gdad gdde | =fefg fc (3ccc | ^fgag fdcA | g3 a gd (3ddd | gdad gdde | =f4 g4 | abag ^fdcA :|  