A large crowd of people are walking.
A large crowd is touring a museum.
Walking does not imply touring a museum.
exists e1 s1 x1 x2.(Actor(e1,x1) & v_walk(e1) & of(x1,x2) & n_people(x2) & n_crowd(x1) & a_large(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_tour(e1) & n_museum(x2) & n_crowd(x1) & a_large(s1) & Theme(s1,x1))