Develop a musical piece that combines the given theme and letter-structured outline.
X:1
L:1/8
M:2/2
K:Eb
['[GB]4 [Gc]4 z3/2 G<Be/ g>fe>c (Be)', 'z2 (GB- B>)GF>G E2- E>FG>A (Be- e']  
X:1
L:1/8
M:2/2
K:Eb
 [GB]4 [Gc]4 | z3/2 G<Be/ g>fe>c | (Be) z c B>GE>G | F>=EF>G F2 B,2 | [GB]4 [Gc]4 | 
 z3/2 G<Be/ g>fe>c | (Be) z2 (GB) z2 | B,>=B,C>D E2 z2 :: (GB- B>)GF>G | E2- E>FG>A | 
 (Be- e e>)dc>e | B8 | B>gf>e d>ec>e | B>ec>B c>BG>B | B,4- B,>CE>F | G>EF>G E2 z2 :|  