Design a musical work that abides by the outlined structure and integrates the assigned theme.
X:1
L:1/4
Q:1/8=120
M:4/4
K:Bb
['B G', 'B A'  
X:1
L:1/4
Q:1/8=120
M:4/4
K:Bb
"^as writ" d/e/ B/G/ | A G D E | F G G B | B G d B | A d e B | G g e c | e e d B | d c A G | G :: 
 B B/B/ B A A/A/ A | G A B A | G F G A | B A G F |"^DE" G :|  