A crowd of people is walking through a parking lot at night.
There are people swimming in a pool.
one cannot be walking and swimming simultaneously.
exists e1 x1 x2 x3 x4 x5.(at(e1,x5) & n_night(x5) & through(e1,x3) & n_lot(x3) & of(x3,x4) & n_parking(x4) & Actor(e1,x1) & v_walk(e1) & of(x1,x2) & n_people(x2) & n_crowd(x1))
exists p1 x1 e1 x2 x3 x4.((x1 = x2) & in(e1,x4) & n_pool(x4) & Actor(e1,x3) & v_swim(e1) & (x2 = x3) & n_people(x2))