Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/4
Q:1/2=100
M:3/2
K:D
['d2 (f/e/)(d/c/) (d/e/) f f2 (a/g/)(f/e/)', 'g f']  
X:1
L:1/4
Q:1/2=100
M:3/2
K:D
 d2 (f/e/)(d/c/) (d/e/) f | f2 (a/g/)(f/e/) f/g/ a | A2 B A g f | e/f/g/a/ b d c2 | 
 d2 (f/e/)(d/c/) (d/e/) f | f2 (a/g/)(f/e/) (f/g/) a | A2 B A g f | e d A c d2 || f2 b f g f | 
 e2 a e f e | ^g2 a d c B | c/A/B/c/ d/e/f/^g/ a2 | A2 B A g f | A2 B A g f | b2 a d A c | d4 |]  