Two men pass on the street.
they are walking
You can't infer they were walking
exists e1 x1 x2.(n_street(x2) & on(e1,x2) & Actor(e1,x1) & v_pass(e1) & n_man(x1) & card_eq_2(x1))
exists e1 x1.(n_thing(x1) & Actor(e1,x1) & v_walk(e1))