People are crossing the street on foot and on a bicycle.
People are crossing the street.
in both sentences, people are crossing the street.
exists e2 e1 x1 x2 x3 x4 x5 x6.(n_street(x5) & n_street(x2) & on(e2,x6) & n_bicycle(x6) & Theme(e2,x5) & Actor(e2,x4) & v_cross(e2) & n_people(x4) & on(e1,x3) & n_foot(x3) & Theme(e1,x2) & Actor(e1,x1) & v_cross(e1) & n_people(x1))
exists e1 x1 x2.(n_street(x2) & Theme(e1,x2) & Actor(e1,x1) & v_cross(e1) & n_people(x1))