two male skaters walk on sidewalk
Two male skaters are exercising.
Just because two male skaters are walking does not imply they are exercising.
exists e1 s1 x1 x2.(on(e1,x2) & n_sidewalk(x2) & Actor(e1,x1) & v_walk(e1) & n_skater(x1) & a_male(s1) & Theme(s1,x1) & card_eq_2(x1))
exists e1 s1 x1.(Actor(e1,x1) & v_exercise(e1) & n_skater(x1) & a_male(s1) & Theme(s1,x1) & card_eq_2(x1))