Construct a melodic piece using the designated alphabetic pattern and the provided musical theme.
X:1
L:1/8
M:6/8
K:G
['Bcd g3', 'BAB GEE']  
X:1
L:1/8
M:6/8
K:G
|:"_Brisk" Bcd g3 | Bcd g3 | Bcd efg | aAA A3 | Bcd g3 | Bcd g3 | dcB ABc | BGG G3 :: BAB GEE | 
 GEE GEE | BAB GEE | FDD D3 | BAB GEE | FAG FED | g3 dAc | BGG G3 :|  