Construct a melodic piece using the designated alphabetic pattern and the provided musical theme.
X:1
L:1/8
Q:1/4=220
M:2/4
K:G
['D2 G2 B3 A B2 c2 B2', 'DFA DFA']  
X:1
L:1/8
Q:1/4=220
M:2/4
K:G
 D2 G2 | B3 A | B2 c2 | B2 A2 | D2 F2 | A3 G | A2 B2 | G4 ::[M:6/8] DGB DGB | DGB B2 A | DFA DFA | 
 DFA G3 :|  