Three bicyclists turn on a curve.
There are four bicyclists
four and three are different numbers
exists e1 x1 x2.(on(e1,x2) & n_curve(x2) & Actor(e1,x1) & v_turn(e1) & n_bicyclist(x1) & card_eq_3(x1))
exists p1 x1 x2.((x1 = x2) & n_bicyclist(x2) & card_eq_4(x2))