Several people walk up a staircase.
People are going up.
Group of people are walking up a staircase
exists e1 s1 s2 x1 x2.(a_up(s2) & Manner(e1,s2) & Theme(e1,x2) & Actor(e1,x1) & v_walk(e1) & n_staircase(x2) & n_people(x1) & a_several(s1) & Theme(s1,x1))
exists e1 s1 x1.(a_up(s1) & Manner(e1,s1) & Actor(e1,x1) & v_go(e1) & n_people(x1))