Compose tunes based on the given letter-based musical structure and the supplied motif.
X:1
L:1/8
M:2/4
K:G
['G BBdd AAcc', 'FAd d d/c/B B/A/G Gc eg d/c/B/c/']  
X:1
L:1/8
M:2/4
K:G
 G | BBdd | AAcc | BGcA | FAd :: d | d/c/B B/A/G | Gc eg | d/c/B/c/ d/e/d/e/ | dgdG | BBdd | AAcc | 
 B/c/d/c/ B/c/d/c/ | BgG :|  