There are several people going up the escalator.
People are at a mall on an escalator
Not all people are at the mall.
exists p1 x1 x4.(n_escalator(x4) & exists e1 s1 s2 x2 x3.((x1 = x2) & Time(e1,x4) & a_up(s2) & Manner(e1,s2) & Actor(e1,x3) & v_go(e1) & (x2 = x3) & n_people(x2) & a_several(s1) & Theme(s1,x2)))
exists p1 x1.(exists x2 x3.(at(x1,x2) & on(x2,x3) & n_escalator(x3) & n_mall(x2)) & n_people(x1))