People are taking pictures of something.
The people are tourists.
Not all people who are taking pictures are tourists.
exists e1 x1 x2 x3.(of(e1,x3) & n_thing(x3) & Theme(e1,x2) & Actor(e1,x1) & v_take(e1) & n_picture(x2) & n_people(x1))
exists p1 x1.(n_people(x1) & exists x2.((x1 = x2) & n_tourist(x2)))