A girl in a helmet rides a horse.
A kid riding a horse.
A kid can be a girl.     Rides and riding is the same action.
exists e1 x1 x2 x3.(Theme(e1,x3) & Actor(e1,x1) & v_ride(e1) & n_horse(x3) & in(x1,x2) & n_helmet(x2) & n_girl(x1))
exists e1 x1 x2 x3.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_ride(e1) & n_horse(x3) & (x1 = x2) & n_kid(x1))