Multiple students sitting on stairs at a school.
The students are sitting outside in the grass.
Students can't be outside in grass and sitting on stairs in school at the same time.
exists e1 x1 x2 x3 x4 x5.(a_topic(x1) & at(e1,x5) & n_school(x5) & on(e1,x4) & n_stair(x4) & Actor(e1,x3) & v_sit(e1) & (x1 = x3) & n_student(x1) & (x1 = x2) & ne_nam_multiple(x2))
exists e1 s1 x1 x2.(n_grass(x2) & n_student(x1) & in(e1,x2) & a_outside(s1) & Manner(e1,s1) & Actor(e1,x1) & v_sit(e1))