Three passengers on a train car.
The people are in their cars.
Cars are different vehicles than a train car.
exists x1 x2 x3.(a_topic(x1) & on(x1,x2) & n_car(x2) & of(x2,x3) & n_train(x3) & n_passenger(x1) & card_eq_3(x1))
exists p1 x1 x2.(n_car(x2) & of(x2,x1) & n_thing(x1) & n_people(x1) & in(x1,x2))