Develop a musical composition based on the provided pattern of letters and incorporating the given motif within it.
X:1
L:1/8
M:4/4
K:D
['B AF cB AG F2 E2 D2', 'fd fa']  
X:1
L:1/8
M:4/4
K:D
 B |:"D" AF Ad"A7" cB AG |"D" F2 (3DFD"A7" E2 D2 |"D" AF Ad"G" BG Bd |"A7" cA Bc"D" d3 B | 
"D" AF Ad"A7" cB AG |"D" F2 (3DFD"A7" E2 D2 |"D" AF Ad"G" BG Bd |1"A7" cA Bc"D" d3 B :|2 
"A7" cA Bc"D" de"A7" fg |:"D" a2 fd fa fd | fa (3gbg"A7" e3 f | ge (3ege c2 ag | 
"D" fg"A7" fe"D" de"A7" fg |"D" a2 fd fa fd | fa (3gbg"A7" e3 f | ge (3ege c2 ag | 
"D" fa"A7" fe"D" d4 :|  