Compose tunes based on the given letter-based musical structure and the supplied motif.
X:1
L:1/4
M:4/4
K:D
['B A']  
X:1
L:1/4
M:4/4
K:D
 d | B A G E | D2 F d | F A G E | D3 F/G/ | A A (F/G/) A | (d3/2 e/) f (f/e/) | d B A F | 
 A2 z (F/G/) | A3/2 F/ A A | (d3/2 e/) f e | d3/2 B/ A F | A2 z d | B A G E | D2 F/ z/ d | 
 F B A (F/E/) | D3 z |]  