Construct a musical composition following the given alphabetical structure and incorporating the specified motif.
X:1
L:1/8
M:2/4
K:Bb
['B2 F2']  
X:1
L:1/8
M:2/4
K:Bb
 ddcc | B2 F2 | ddcc | B2 F2 | d2 cc | B2 F2 | ddcc | B2 F2 | ccAA | ffdd | eecc | f4 |]  