A number of people cross in front of the top of an escalator.
The people are at the airport.
Because people are crossing in front of escalator doesn't mean they are at the airport.
exists e1 x1 x2 x3 x4 x5.(n_top(x4) & in(e1,x3) & of(x3,x4) & of(x4,x5) & n_escalator(x5) & n_front(x3) & Actor(e1,x1) & v_cross(e1) & of(x1,x2) & n_people(x2) & n_number(x1))
exists p1 x1 x2.(n_airport(x2) & n_people(x1) & at(x1,x2))