Form a musical piece based on the provided motif while observing the defined structure.
X:1
L:1/16
M:2/4
K:G
['B4 A4 G4 G4', 'B2G2 A2D2 G2G2', '(Bd)(cB) (Ac)(BA) G2G2'  
X:1
L:1/16
M:2/4
K:G
 (dc) | B4 A4 | G4 G4 (cB)(AG) | F2A2 A2(dc) | B4 A4 | G4 G4 A2B2c2A2 | B2G2 G2 :: (dc) | 
 B2G2 A2D2 | G2G2 (c2B2)(A2G2) | F2A2 A2(BA) | B2G2 A2D2 | G2G2 (AB)(cA) | B2G2 G2 :: (dc) | 
 (Bd)(cB) (Ac)(BA) | G2G2 (cB)(AG) | F2A2 A2(dc) | (Bd)(cB) (Ac)(BA) | G2G2 ABcA | B2G2 G2 :|  