Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
Q:1/4=120
M:2/4
K:G
['G/A/B/c/ dg dBBg', 'G/A/B/c/ dB', 'gd B/c/d/B/']  
X:1
L:1/8
Q:1/4=120
M:2/4
K:G
 G/A/B/c/ dg | dBBg | dBBg | d2 B2 | G/A/B/c/ dg | dBBg | =fAAB | c2 A2 :: G/A/B/c/ dB | ed/c/ dB | 
 G/A/B/c/ dB | d2 B2 | G/A/B/c/ dB | ed/c/ de | =fAAB | cA :: gd B/c/d/B/ | gd B/c/d/B/ | 
 gd B/c/d/B/ | d2 B2 | gd B/c/d/B/ | gd B/c/d/B/ | aAAB | c2 A2 :|  