Guys are running in a marathon.
The guys are walking
Running and walking are two different actions.
exists e1 x1 x2.(in(e1,x2) & n_marathon(x2) & Actor(e1,x1) & v_run(e1) & n_guy(x1))
exists e1 x1.(n_guy(x1) & Actor(e1,x1) & v_walk(e1))