Another man in a gray sweatshirt also rides a horse.
There are multiple people with animals
Another man with a horse makes it be several horses and multiple people.
exists e1 s1 s2 x1 x2 x3 x4.(n_man(x1) & a_also(s2) & Manner(e1,s2) & Theme(e1,x4) & Actor(e1,x2) & v_ride(e1) & n_horse(x4) & in(x2,x3) & n_sweatshirt(x3) & a_gray(s1) & Theme(s1,x3) & n_man(x2) & -(x2 = x1))
exists p1 x1 s1 x2 x3.((x1 = x2) & with(x2,x3) & n_animal(x3) & n_people(x2) & a_multiple(s1) & Theme(s1,x2))