Bike riders stop riding while one rider fixes bike.
Bike riders racing downhill.
The bikers cannot be stopped and also racing downhill.
exists e1 p1 x1 x2.(exists e2 p2.(exists e3 x3 x4.(Theme(e3,x4) & Actor(e3,x3) & v_fix(e3) & n_bike(x4) & n_rider(x3) & card_eq_1(x3)) & while(e2,p2) & Actor(e2,x1) & v_ride(e2)) & Topic(e1,p1) & Actor(e1,x1) & v_stop(e1) & n_rider(x1) & (x1 = x2) & ne_nam_bike(x2))
exists e1 x1 x2 x3 x4.(a_topic(x1) & Theme(e1,x4) & Actor(e1,x3) & v_race(e1) & n_downhill(x4) & (x1 = x3) & n_rider(x1) & (x1 = x2) & ne_nam_bike(x2))