Construct a musical composition following the given alphabetical structure and incorporating the specified motif.
X:1
L:1/8
M:6/8
K:Bb
['F B2 dccB A2 B c3 B>cdd>cB']  
X:1
L:1/8
M:6/8
K:Bb
 F | B2 dccB | A2 B c3 | B>cdd>cB | c3- c2 d | deffed | cee e3 | ddddcB | Acc c3 | B>cddcB | 
 B3- B2 |]  