Given the composition on the left, and the AQL query after that, what should the result set for the select clause on the right be? Same as before: think on it whenever you have some free time
SELECT c,s,i_1,i_2 FROM COMPOSITION C c CONTAINS SECTION s CONTAINS (INSTRUCTION i_1 AND INSTRUCTION i_2)
<c|s|i|i|i>(i) on the leftmost tree is composition|section|instruction(x3) instances, i.e. a single composition instance.