Create a musical composition employing the given alphabetic structure and melodic theme.
X:1
L:1/8
M:4/4
K:G
['GA BcAB GAFG EFGA B2 ef']  
X:1
L:1/8
M:4/4
K:G
"^A" GA |"Em" BcAB GAFG |"Em" EFGA B2 ef |"Em" gfed"G" edBd |"Am" cBAG"B7" A2 GA |"Em" BcAB GAFG | 
"Em" EFGA B2 ef |"Am" gfed"B7" Bgf<g |"Em" e4 e2 :|"^B" ga |"Em" b^abg efga |"Em" b^abg e2 fe | 
"D" d^cde fefg |"D" afdf a2 gf |"Em" eBeg"D" fdfa |"G" gfga b2 ef |"Am" gfed"B7" Bgf<g | 
"Em" e4 e2 :|  