Develop a musical composition utilizing the presented motif and adhering to the required structure.
X:1
L:1/8
M:4/4
K:G
['B2 GA B2 AG A2', 'B2 GA B2 cB'  
X:1
L:1/8
M:4/4
K:G
 B2 GA B2 AG | A2 c2 B2 G2 | B2 GA B2 AG | A2 d2 B4 :: B2 GA B2 cB | A2 GF E2 D2 | B2 GA B2 cB | 
 AGFD E4 :|  