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:D
['ABde f2', 'afdf a2 gf']  
X:1
L:1/8
M:2/2
K:D
 d | ABde f2 ed | f2 ed Beef | ABde f2 ec | dBAF D/D/D D2 :| f/g/ | afdf a2 gf | efga bgef/g/ | 
 afdf a2 gf | geag fddf/g/ | afdf a2 gf | gafg edef | dBAF ABdA | Bgfe fdd ||  