Two boys are riding bikes down a sidewalk.
Children are racing outside.
Riding does not have to mean racing.
exists e1 x1 x2 x3.(down(e1,x3) & n_sidewalk(x3) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2) & n_boy(x1) & card_eq_2(x1))
exists e1 p1 x1.(exists s1.(Theme(s1,x1) & a_outside(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_race(e1) & n_child(x1))