Construct a musical composition following the given alphabetical structure and incorporating the specified motif.
X:1
L:1/8
M:2/4
K:Bb
['d2 c2']  
X:1
L:1/8
M:2/4
K:Bb
 BFBc | d2 c2 | B4 | dcde | f2 gf | edcd | e2 fe | dcBc | d2 c2 | B4 |]  