An elderly person walks beside a city building pulling a cart behind them.
An old person runs the Boston marathon.
The person that walks on a sidewalk would not be able to run a marathon at the same time.
exists e1 e2 s1 x1 x2 x3 x4.(for(e1,e2) & behind(e2,x1) & n_thing(x1) & Theme(e2,x4) & Actor(e2,x1) & v_pull(e2) & n_cart(x4) & beside(e1,x2) & n_building(x2) & of(x2,x3) & n_city(x3) & Actor(e1,x1) & v_walk(e1) & n_person(x1) & a_elderly(s1) & Theme(s1,x1))
exists e1 s1 x1 x2 x3.(n_marathon(x2) & (x2 = x3) & ne_geo_boston(x3) & Theme(e1,x2) & Actor(e1,x1) & v_run(e1) & n_person(x1) & a_old(s1) & Theme(s1,x1))