Construct a musical piece by amalgamating the designated alphabetical representation and the supplied musical theme.
X:1
L:1/8
M:4/4
K:G
['G3 B', 'd3 B']  
X:1
L:1/8
M:4/4
K:G
|: GA | B2 D2 G3 B | G6 AB | c3 B/A/ B3 A/G/ | F2 A2 D4 | cBAG GFED | G3 B E2 c/B/A | 
 B2 (3GAB A z FE/F/ | G6 :| Bc | d3 B d3 B | c/d/e- e2 A2 Bc | d3 G F2 G2 | AGFE D2 Bc | 
 d3 B d3 B | c/d/e- e2 e/f/g- g2 | fgag fdef | g6 ga | b2 g2 d3 B |[M:6/4] c2 de A6 Bc | 
[M:4/4] d3 G F2 G2 | AGFE D3 c | B3 G d3 B |[M:6/4] c2 de A6 dc/A/ |[M:4/4] B2 ga/b/ a2 fe/f/ | 
 g6 ||  