Two children run and play in the grass.
Children sit in a classroom.
run and sit are different activity
exists e2 e1 x1 x2 x3.(n_grass(x3) & in(e2,x3) & Actor(e2,x2) & v_play(e2) & n_child(x2) & card_eq_2(x2) & Actor(e1,x1) & v_run(e1) & n_child(x1) & card_eq_2(x1))
exists e1 x1 x2.(in(e1,x2) & n_classroom(x2) & Actor(e1,x1) & v_sit(e1) & n_child(x1))