A pair is performing in a ballet.
The stars of a ballet troupe are performing a Tchaikovsky ballet.
It cannot be inferred that the pair are stars or that they are performing a Tchaikovsky ballet.
exists e1 x1 x2.(in(e1,x2) & n_ballet(x2) & Actor(e1,x1) & v_perform(e1) & n_pair(x1))
exists e1 x1 x2 x3 x4 x5.(n_star(x1) & Theme(e1,x4) & Actor(e1,x1) & v_perform(e1) & n_ballet(x4) & (x4 = x5) & ne_org_tchaikovsky(x5) & of(x1,x2) & n_troupe(x2) & of(x2,x3) & n_ballet(x3))