Four people sit at a table.
Four people are eating dinner at a table.
Sometimes people sit at tables and do not eat dinner.
exists e1 x1 x2.(at(e1,x2) & n_table(x2) & Actor(e1,x1) & v_sit(e1) & n_people(x1) & card_eq_4(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_eat(e1) & at(x2,x3) & n_table(x3) & n_dinner(x2) & n_people(x1) & card_eq_4(x1))