People gather and talk in the street.
The street is completely empty
If people gather in the street, it is no longer empty.
exists e1 e2 x1 x2 x3.(n_street(x3) & in(e2,x3) & Actor(e2,x2) & v_talk(e2) & n_people(x2) & Actor(e1,x1) & v_gather(e1) & n_people(x1))
exists s1 x1.(n_street(x1) & r_completely(s1) & Theme(s1,x1) & a_empty(s1))