Create a musical composition adhering to the provided thematic and alphabetical guidelines.
X:1
L:1/8
Q:1/4=140
M:2/4
K:Bb
['B2 (3dcB']  
X:1
L:1/8
Q:1/4=140
M:2/4
K:Bb
 B2 (3dcB | g>edc | B2 (3dcB | AFAF | B2 (3dcB | g>edc | (3def (3dcB | Tc2 B2 |:  