Construct a melodic piece using the designated alphabetic pattern and the provided musical theme.
X:1
L:1/16
M:2/4
K:G
['d2^d2 e4 z dcA D4 z2 _E2', 'DG z B AGBG']  
X:1
L:1/16
M:2/4
K:G
 d2^d2 e4 | z dcA D4 | z2 _E2 (=Ec)zc | BGAF GABc | d2^d2 e4 | z dcA D4 | z2 _E2 (=Ec) z c | 
 BGAF G2 z2 :: DG z B AGBG | DB aB AGBG | Ad z f edfd | Ad z f edfd | DG z B AGBG | DG z B AGBG |1 
 egga gedc | BGAF GFED :|2 (3dcB (3Bcd cBAc | BGAF GABc ||  