Two boys rollerblading.
The boys are riding bikes.
either the boys are rollerblading or riding bikes
exists e1 x1.(Actor(e1,x1) & v_rollerblade(e1) & n_boy(x1) & card_eq_2(x1))
exists e1 x1 x2.(n_boy(x1) & Theme(e1,x2) & Actor(e1,x1) & v_ride(e1) & n_bike(x2))