Three little boys on a float in a river.
boys head down the river in a raft
Just because boys are in the river doesn't necessarily mean they have to head down the river. There are many objects to float on other than a raft.
exists s1 x1 x2 x3.(a_topic(x1) & on(x1,x2) & in(x2,x3) & n_river(x3) & n_float(x2) & n_boy(x1) & a_little(s1) & Theme(s1,x1) & card_eq_3(x1))
exists e1 x1 x2 x3.(n_river(x2) & down(e1,x2) & in(x2,x3) & n_raft(x3) & Actor(e1,x1) & v_head(e1) & n_boy(x1))