Write a musical work incorporating the specified theme and letter-based framework.
X:1
L:1/8
M:9/8
K:D
['F2 FD', 'B2 BA']  
X:1
L:1/8
M:9/8
K:D
|: F2 FD GE | F2 FD ED | F2 F2 GB | AF DF ED :: B2 BA GA | BE ED GA | B2 BA GB | AD DE FD :|  