Several people in a restaurant.
People are outside walking.
If the people are outside walking they cannot be in the restaurant at the same time.
exists s1 x1 x2.(a_topic(x1) & in(x1,x2) & n_restaurant(x2) & n_people(x1) & a_several(s1) & Theme(s1,x1))
exists p1 x1.(exists s1 x2.((x1 = x2) & n_walking(x2) & a_outside(s1) & Theme(s1,x2)) & n_people(x1))