People are water painting their arms.
people prepare for festival
Painting their arms is not necessarily to prepare for festival.
exists e1 p1 x1 x2.(for(p1,e1) & Theme(e1,x2) & Actor(e1,x1) & v_paint(e1) & n_arm(x2) & of(x2,x1) & n_thing(x1) & exists x3.((x1 = x3) & n_water(x3)) & n_people(x1))
exists e1 x1 x2.(for(e1,x2) & n_festival(x2) & Actor(e1,x1) & v_prepare(e1) & n_people(x1))