Kids are playing video games.
A teacher is grading papers.
A teacher won't be a kid.
exists e1 x1 x2 x3.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_game(x2) & of(x2,x3) & n_video(x3) & n_kid(x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_grade(e1) & n_papers(x2) & n_teacher(x1))