Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/16
M:2/4
K:G
['B2E2 EFGA']  
X:1
L:1/16
M:2/4
K:G
 D2 |"G" G2GF GABc |"G" dBge dBGA |"Em" B2E2 EFGA |"Em" BAGB"D7" AGED |"G" G2GF GABc | 
"G" dBge dBGA |"Em" B2E2 EFGA |"D7" BGAF"G" G2 :: GG |"Em" B2e2 edef |"Em" geaf gfed | 
"D" A2d2 d^cde |"D" fdaf gfed |"Em" B2e2 edef |"Em" geaf gfed |"Em" B2E2 EFGA |"D7" BGAF"G" G2 :|  