Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
M:2/2
K:C
['dBA B2 G']  
X:1
L:1/8
M:2/2
K:C
 G |"C" c2 e c2 e |"Am" ecA A2 A |"G" Bcd dBG |1"G" Bcd dBG :|2"C" c3 c2 |]: d |"C" cBA"G" GAB | 
"G" dBA B2 G |"C" cBA"G" GAB |"C" cBA"G" GAB | |"G" dBA B2 G |"G" dBA B2 G |"C" cBA"G" GAB | 
"C" c3 c2 :|  