Write musical pieces that adapt to the predetermined chord shifts.
'A', 'D', 'A', 'D', 'A', 'D', 'E', 'A', 'D', 'A', 'D', 'A', 'D', 'E'  
X:1
L:1/8
M:2/4
K:A
"A" A>B cA |"D" BA ce |"A" A>B cA |"D" BA F2 |"A" A>B cA |"D" BA ce | A>B AF |"E" FE E2 :: 
"A" e>f ec |"D" BA Bc |"A" e>f ec |"D" BA F2 |"A" e>f ec |"D" BA Bc | A>B AF |"E" FE E2 :|  