Develop a musical composition by integrating the alphabetically represented musical pattern and the supplied melodic theme.
X:1
L:1/8
M:2/4
K:Bb
['B2 d2', 'c3 d', 'FF DF Bd f2 f=e cd']  
X:1
L:1/8
M:2/4
K:Bb
"^A""^bestimmt" F2 | (B2 B/)c/d/e/ | f3 d | f/=e/c/(d/ d2) | B2 d2 | F4 | DF Bd | c2 e2 | F4 | 
 EF dc | B2 d2 | (F4 | !breath!F2) F2 | (B2 B/)c/d/e/ | f3 d | f/=e/c/(d/ d2) | B2 d2 | F4 | 
 DF Bd | c2 e2 | F4 | f3 =e | c d3 | (!fermata!B4 | B2) ||[M:3/4]"^B""^LA$?ndlertempo" d2 f=e | 
 c3 d F2 | c2 f=e cd | B3 c d2 | F3 D Fd | c3 d e2 | F3 f dc | B3 A Bc | (d6 | !breath!d2) d2 f=e | 
 c3 d F2 | c2 f=e cd | B3 c d2 | F3 D Fd | c3 d e2 | F2"^rit." d2 c2 | !fermata!B6 || 
[M:3/4]"^C" F2 FF FF | DF Bd f2 | f=e cd cF | BA Bc d2 | F2 FF FF | DF Bd f2 | f=e cd cF | B6 | 
 F2 FF FF | DF Bd f2 | f=e cd cFBA Bc d2 | F2 FF FF | DF Bd f2 | f=e cd cF | !fermata!B6 |]  