People stroll outdoors at the airport.
There are people at an airport
People are in an airport.
exists e1 x1 x2 x3.(n_airport(x3) & at(e1,x3) & Theme(e1,x2) & Actor(e1,x1) & v_stroll(e1) & n_outdoors(x2) & n_people(x1))
exists p1 x1 x2 x3.((x1 = x2) & at(x2,x3) & n_airport(x3) & n_people(x2))