Several children work on a project with painted shells.
children are painting
to work on a project implies the action is not finished.  so does painting
exists e1 s1 s2 x1 x2 x3.(on(e1,x2) & with(x2,x3) & n_shell(x3) & a_painted(s2) & Theme(s2,x3) & n_project(x2) & Actor(e1,x1) & v_work(e1) & n_child(x1) & a_several(s1) & Theme(s1,x1))
exists e1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_paint(e1) & n_thing(x2) & n_child(x1))