Design a musical work that abides by the outlined structure and integrates the assigned theme.
X:1
L:1/4
Q:1/4=120
M:3/4
K:Bb
['(D3 D3) D3']  
X:1
L:1/4
Q:1/4=120
M:3/4
K:Bb
 (D3 | D3) | D3 | (D3 | D3) | D3 | (D3 | D3) | D3 | F3 | B3/2 c3/2 | B3 | B c d | F2 E | D3 | 
 B c d | F2 E | D2 D | F2 E | D3 | C3 | F G A | B2 B | c2 c | d2 d | e3 | d c B | G2 G | (G3 | 
 A3) | B3 |]  