Design a musical composition incorporating the alphabetic expression of the chosen structure and the provided melodic theme.
X:1
L:1/8
M:6/8
K:A
['B2 B B>cd']  
X:1
L:1/8
M:6/8
K:A
 E |"A" A2 A A>GA |"E7" B2 B B>cd |"A" c>BA"E7" G>AB | E2 E E>FG |"A" A2 A A>GA |"E7" B2 B B>cd | 
"A" c>BA"E7" B>AG |"A" A3"B7" A2 B ||[K:E]"E" e2 e e>fg |"B7" f2 f f>ga |"E" g>fe"B7" d>ef | 
"E" B2 B B>cd | e2 e e>fg |"B7" f2 f f>ga |"E" g>fe"B7" f>ed |"E" e3 e2 z ||[K:A]"A" e2 e e>fe | 
"E7" d2 d d>ed |"A" c2 c c>dc |"E7" B2 B B>cd | e2 e e>fe |"Bm" d2 d d>ef |"E7" e>dc B>AG | 
"A" A3 A2 z |]  