Construct a musical piece by amalgamating the designated alphabetical representation and the supplied musical theme.
X:1
L:1/4
M:3/4
K:G
['G3/2 A/ G G A B c3/2', 'B G A F']  
X:1
L:1/4
M:3/4
K:G
 D/ | G3/2 A/ G | G A B | c3/2 c/ c | c2 A | B3/2 c/ d | d c B | (A/B/).A/.G/.F/.E/ | 
 (E/F/)E/C/B,/A,/ | G3/2 A/ G | G A B | c3/2 c/ c | c2 A | d c B | A/B/A/G/F/A/ | G2 :: 
[M:2/4]"^Allegro" d2 | B G A F | (G/A/).G/.F/ G d | B G A F | G2 d2 | B G A F | (G/A/)G/F/ G d | 
 B G A F | G2 ::  