Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
M:3/4
K:G
['B2 BdBG', 'GBdB c2 A2 cA F2 FAcA']  
X:1
L:1/8
M:3/4
K:G
 DG | B2 BdBG | B2 BdBG | A2 AcBA |1 B2 G2 :|2 G4 |: dB | G2 GBdB | c2 A2 cA | F2 FAcA | B2 G2 dB | 
 G2 GBdB | c2 A2 cA | F2 FAcA | G4 :|  