The four hikers walked up the gravel road.
Four hikers walk up a road.
Walked and walk are the same thing.
exists e1 s1 x1 x2 x3.(n_road(x2) & of(x2,x3) & n_gravel(x3) & n_hiker(x1) & card_eq_4(x1) & a_up(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_walk(e1))
exists e1 x1 x2.(up(e1,x2) & n_road(x2) & Actor(e1,x1) & v_walk(e1) & n_hiker(x1) & card_eq_4(x1))