four boys looking out from a boat.
Some boys are in a boat.
'Some' is a good replacement for four.
exists e1 s1 x1 x2.(a_out(s1) & Manner(e1,s1) & from(e1,x2) & n_boat(x2) & Actor(e1,x1) & v_look(e1) & n_boy(x1) & card_eq_4(x1))
exists p1 x1.(exists x2.(in(x1,x2) & n_boat(x2)) & n_boy(x1))