Three women participate in a roller derby.
Three women are wearing roller skates.
The women must be wearing roller skates on order to participate in a roller derby.
exists e1 x1 x2 x3.(in(e1,x2) & n_derby(x2) & of(x2,x3) & n_roller(x3) & Actor(e1,x1) & v_participate(e1) & n_woman(x1) & card_eq_3(x1))
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_wear(e1) & n_skate(x2) & of(x2,x3) & n_roller(x3) & n_woman(x1) & card_eq_3(x1))