Utilizing the provided musical theme and letter-based structure, compose a piece of music.
X:1
L:1/8
M:6/8
K:G
['B2 B Bgf e2 e efg']  
X:1
L:1/8
M:6/8
K:G
 dcS |"G" B2 B Bgf |"C" e2 e efg |"G" ded"Em" dcB |"Am" cBc"D7" Adc |"G" B2 B Bgf |"C" e2 e efg | 
"G" ded"D7" cBA |"G" GAG G :| ga |"G" b2 g"D7" a2 f |"C" gfe"D7" d2 c |"G" Bdg"G" dBG | 
"D7" FAA A2 ga |"G" b2 g"D7" a2 f |"C" gfe"D7" agf |"G" bag"A7" fge |"D7" dgf edSc |]  