A young girl wearing a helmet and riding a brown horse.
The girl is running alongside the horse.
One cannot be riding on a horse and running alongside the horse at the same time.
exists e2 e1 s1 s2 x1 x2 x3 x4 x5.(a_topic(x1) & Theme(e2,x5) & Actor(e2,x4) & v_ride(e2) & n_horse(x5) & a_brown(s2) & Theme(s2,x5) & (x1 = x4) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & n_helmet(x3) & (x1 = x2) & n_girl(x1) & a_young(s1) & Theme(s1,x1))
exists e1 x1 x2.(n_horse(x2) & n_girl(x1) & alongside(e1,x2) & Actor(e1,x1) & v_run(e1))