Two people walk outside in a nature area.
The two people are walking down a sidewalk.
Sidewalks are not present in nature areas, therefore two people cannot be walking down a sidewalk in a nature area.
exists e1 x1 x2 x3 x4.(a_topic(x1) & in(e1,x4) & n_nature(x4) & outside(e1,x3) & n_area(x3) & Theme(e1,x2) & v_walk(e1) & (x1 = x2) & n_people(x1) & card_eq_2(x1))
exists e1 s1 x1 x2.(n_people(x1) & card_eq_2(x1) & a_down(s1) & Manner(e1,s1) & Theme(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_sidewalk(x2))