There are 4 horses in the photo.
A group of animals.
4 horses are not necessarily a group.
exists p1 x1 x2.(n_photo(x2) & in(p1,x2) & exists x3.((x1 = x3) & n_horse(x3) & n_date(x3) & a_date_day_04(x3) & a_date_day_04(x3)))
exists x1 x2.(a_topic(x1) & of(x1,x2) & n_animal(x2) & n_group(x1))