Construct a musical piece that follows the designated lettered structure and integrates the provided motif throughout.
X:1
L:1/8
Q:1/8=140
M:6/8
K:Emin
['e2 f', 'efg BAG FED D2 d d^cd Eee', 'FED E/E/Eb gfe d/c/B/A/B/d/ e/f/gb g>fe/d/ f>ed/B/']  
X:1
L:1/8
Q:1/8=140
M:6/8
K:Emin
"^allegro ma non troppo" E | Eed e2 f | gba gfe | dBA G/A/BA | GFG E2 D |"^5" E2 c dcd | 
 E2 e e2 f | Bba b2 a | gfe e2 || g |"^9" fed efg | BAG FED | D2 d d^cd | Eee ed/B/A/F/ | 
"^13" E/F/GE E/F/GE | D/E/FD D/E/FD | F/B/BA GFE | DB,B, B,2 || D |"^17" E/E/Ee E/E/Ee | 
 E/E/EA FED | E/E/Eb gfe | d/c/B/A/B/d/ e/f/gb |"^21" g>fe/d/ f>ed/B/ | edB AFD | E/E/Ee E/E/Ee | 
 FDF E2 |]  