Compose tunes based on the given letter-based musical structure and the supplied motif.
X:1
L:1/8
M:2/2
K:G
['GFGA B2 Bc ded^c', 'z gfga g2 ga bgag']  
X:1
L:1/8
M:2/2
K:G
 GFGA B2 Bc | ded^c dg g2 | =FEFG A2 Bc | dedc BGG z | GFGA B2 Bc | ded^c dgga | bgaf gdde | 
 =fdcA BGG z || gfga g2 ga | bgag fdde | =fefg f2 ce | dcBA BGG z | gfga g2 ga | bgag fddg | 
 bgaf gdde | =fdcA BGG z ||  