Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
M:2/2
K:Eb
['E>GB,>E G,>B,E>G B>Gc>B', '=A>gf>e d>ba>b']  
X:1
L:1/8
M:2/2
K:Eb
({uc} B>.=A) | vB>eG>B E>GB,>E | G,>B,E>G B>Gc>B | A>FD>A G>EC>B, | =A,>GF>E F>_A=A>c | 
 B>eG>B E>GB,>E | G,>B,E>G B>Gc>B | A>FD>B, =A,>B,_A,>D | E>B,G,>G E2 ::({uG} F>.=E) | 
 vF>ec>B =A>gf>e | d>ba>b =e>fc>d | e>c=A>e c>AF>E | C3/2{c}B=A>B F>dc>B | F>ec>B =A>gf>e | 
 d>ba>b ^f>ge>c | =e>fd>B =A>FE>C | B,>DF>d B2 :|  