Construct a musical composition utilizing the provided motif and conforming to the specified structure.
X:1
L:1/16
Q:1/4=80
M:2/4
K:G
['GGGG G2A2 BBBB B2c2 dddd d2e2 f6', 'a2g2 g2ff f2e2'  
X:1
L:1/16
Q:1/4=80
M:2/4
K:G
|:"_G" GGGG G2A2 | BBBB B2c2 | dddd d2e2 |"_D7" f6 g2 | aaaa a2g2 | ffff f2e2 | dddd d2c2 | 
"_G" B6 A2 | GGGG G2A2 | BBBB B2c2 | dddd d2e2 |"_D7" f6 g2 | aaaa a2g2 | ffff f2e2 | d2^cd e2f2 | 
"_G" g4 g4 ::"_G" d2gg g2d2 | B2dd d2B2 | G2gg g2B2 |"_C" c6 B2 |"_D7" A2aa a2g2 | g2ff f2e2 | 
 e2dd d2c2 |"_G" B6 d2 | d2gg g2d2 | B2dd d2B2 | G2gg g2B2 |"_C" c6 B2 |"_D7" A2aa a2g2 | 
 g2ff f2e2 | d2^cd e2f2 |"_G" g4 g4 :|  