crowd of people walking in the street
A crowd of people are walking in the street.
people walking means the same as  people are walking.
exists e1 x1 x2 x3 x4.(n_street(x4) & a_topic(x1) & of(x1,x2) & in(e1,x4) & Actor(e1,x3) & v_walk(e1) & (x2 = x3) & n_people(x2) & n_crowd(x1))
exists e1 x1 x2 x3.(n_street(x3) & in(e1,x3) & Actor(e1,x1) & v_walk(e1) & of(x1,x2) & n_people(x2) & n_crowd(x1))