The children played on the four wheeler in the field.
The children are great riders.
playing on the four wheeler in the field is not an indication that the children are great riders.
exists e1 x1 x2 x3.(n_field(x3) & n_wheeler(x2) & card_eq_4(x2) & n_child(x1) & on(e1,x2) & in(x2,x3) & Actor(e1,x1) & v_play(e1))
exists p1 x1.(n_child(x1) & exists s1 x2.((x1 = x2) & n_rider(x2) & a_great(s1) & Theme(s1,x2)))