Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
M:4/4
K:C
['.abc ||[M:2/2][K:D] (3Tf2', 'f2 (de) fBde', 'eBde f^gaf eAce fBdBfBde fBdB eAce dcBc']  
X:1
L:1/8
M:4/4
K:C
 .abc ||[M:2/2][K:D] (3Tf2 (de) fBde | Tf2 (df) eAce |{g} f2 (de) fBde | fgaf eAce | f2 (de) fBde | 
 Tf2 (df) eAce |{g} f2 (de) fBde | fgaf eAce || fBdB fBde | fBdB eAce | fBdB eBde | f^gaf eAce | 
 fBdBfBde | fBdB eAce | dcBc defg | abaf eAce ||  