Construct a melodic piece using the designated alphabetic pattern and the provided musical theme.
X:1
L:1/8
M:2/4
K:Dmix
['A,>B, DE', 'A>G FA Gd']  
X:1
L:1/8
M:2/4
K:Dmix
 F>A GB | AF ED | F/G/A BF | ED B,2 |1 A,>B, DE | FA B2- | BG F/G/F | E2 G2 :|2 A,>B, DE | FD C2- | 
 CE D/E/G | FD D2 |]: f>g af | g/f/e ef | d>B AG | F/G/A B2 |1 A>G FA | Gd c2- | cA, B,/D/E | 
 FD AD :|2 A>G FA | Gd cA,- | A,B, D/E/G | FD D2 ||  