A group of volunteers help build a house on behalf of Habitat for Humanity.
Nobody is building.
Either the group is building OR nobody is building. Cannot be both.
exists e1 p1 x1 x2 x5 x6.(ne_org_humanity(x6) & ne_org_habitat(x5) & exists e2 x3 x4.(for(e2,x6) & on(e2,x4) & of(x4,x5) & n_behalf(x4) & Theme(e2,x3) & Actor(e2,x1) & v_build(e2) & n_house(x3)) & Topic(e1,p1) & Actor(e1,x1) & v_help(e1) & of(x1,x2) & n_volunteer(x2) & n_group(x1))
-exists e1 x1.(Actor(e1,x1) & v_build(e1) & n_person(x1))