Two children without shirts on sit at the edge of a fountain.
Two childless adults are on a canoe in the middle of the ocean.
Children without shirts don't qualify as childless adults. The two persons can't be at the edge of a fountain and in the middle of the ocean simultaneously.
exists e1 x1 x2 x3.(n_edge(x2) & at(e1,x2) & of(x2,x3) & n_fountain(x3) & Actor(e1,x1) & v_sit(e1) & -exists s1 x4 x5.(with(x1,x4) & Theme(s1,x5) & a_on(s1) & (x4 = x5) & n_shirt(x4)) & n_child(x1) & card_eq_2(x1))
exists p1 s1 x1 x2 x3.(n_ocean(x3) & n_middle(x2) & in(p1,x2) & of(x2,x3) & exists x4.(on(x1,x4) & n_canoe(x4)) & n_adult(x1) & a_childless(s1) & Theme(s1,x1) & card_eq_2(x1))