People in costumes are walking around in the street.
People are trick or treating.
Not all people in costumes walking around in the street are trick or treating.
exists e1 p1 x1 x2 x3.(n_street(x3) & in(e1,x3) & exists s1.(Theme(s1,x1) & a_around(s1)) & Topic(e1,p1) & Actor(e1,x1) & v_walk(e1) & in(x1,x2) & n_costume(x2) & n_people(x1))
(exists e1 x1.(Actor(e1,x1) & v_trick(e1) & n_people(x1)) | exists e2 x2.(Actor(e2,x2) & v_treat(e2) & n_people(x2)))