Four people are farming in a field.
They are harvesting crops.
Farming need not always mean harvesting.
exists e1 x1 x2.(in(e1,x2) & n_field(x2) & Actor(e1,x1) & v_farm(e1) & n_people(x1) & card_eq_4(x1))
exists e1 x1 x2.(n_thing(x1) & Theme(e1,x2) & Actor(e1,x1) & v_harvest(e1) & n_crop(x2))