Two people in racing clothes and helmets are riding motorcycles.
Two people are outside.
The people can only be riding motorcycles if they are outside.
exists e1 e2 x1 x2 x3 x4 x5 x6.(Theme(e2,x6) & Actor(e2,x1) & v_ride(e2) & n_motorcycle(x6) & Theme(e1,x3) & Actor(e1,x2) & v_race(e1) & subset_of(x5,x3) & n_helmet(x5) & subset_of(x4,x3) & n_clothes(x4) & (x1 = x2) & n_people(x1) & card_eq_2(x1))
exists s1 x1.(Theme(s1,x1) & a_outside(s1) & n_people(x1) & card_eq_2(x1))