Utilize the provided motif and the alphabetically represented musical sequence to craft an original musical composition.
X:1
L:1/8
M:2/4
K:Bb
['ffgb f3 d cc/d/cb fg/b/ c2 cfcb']  
X:1
L:1/8
M:2/4
K:Bb
 ffgb | f3 d | cc/d/cb | fg/b/ c2 | cfcb | bf g2 | cf/g/cb/g/ | f2 ff | cdf z | f2 cd | f4 |]  