A man walking through an empty classroom.
The classroom does not have students in it
The classroom is empty. There are no students.
exists e1 s1 x1 x2 x3.(a_topic(x1) & through(e1,x3) & n_classroom(x3) & a_empty(s1) & Theme(s1,x3) & Actor(e1,x2) & v_walk(e1) & (x1 = x2) & n_man(x1))
exists x1.(n_thing(x1) & n_classroom(x1) & -exists e1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_have(e1) & in(x2,x1) & n_student(x2)))