a group of people walking down the street.
The people are walking.
People is the plural form of person, and they are walking.
exists e1 x1 x2 x3 x4.(n_street(x4) & a_topic(x1) & of(x1,x2) & down(e1,x4) & Actor(e1,x3) & v_walk(e1) & (x2 = x3) & n_people(x2) & n_group(x1))
exists e1 x1.(n_people(x1) & Actor(e1,x1) & v_walk(e1))