A group is on a canoe on a river.
A boy is swimming in an indoor pool.
A group is not a boy and being on a canoe on a river is different than swimming in a indoor pool.
exists p1 x1.(exists x2 x3.(on(x1,x2) & on(x2,x3) & n_river(x3) & n_canoe(x2)) & n_group(x1))
exists e1 s1 x1 x2.(in(e1,x2) & n_pool(x2) & a_indoor(s1) & Theme(s1,x2) & Actor(e1,x1) & v_swim(e1) & n_boy(x1))