Several men sit while banging on a bongo.
Several men are playing pool.
People cannot be playing pool and banging on a bongo at the same time.
exists e1 e2 s1 x1 x2.(while(e1,e2) & on(e2,x2) & n_bongo(x2) & Actor(e2,x1) & v_bang(e2) & Actor(e1,x1) & v_sit(e1) & n_man(x1) & a_several(s1) & Theme(s1,x1))
exists e1 s1 x1 x2.(Theme(e1,x2) & Actor(e1,x1) & v_play(e1) & n_pool(x2) & n_man(x1) & a_several(s1) & Theme(s1,x1))