Several girls on a raft floating in rough waters.
The girls have on hats.
Sentence one provides no description of the girls floating on the raft so there is no way to know whether one or more girls have on hats.
exists e1 s1 s2 x1 x2 x3 x4.(a_topic(x1) & on(x1,x2) & in(e1,x4) & n_waters(x4) & a_rough(s2) & Theme(s2,x4) & Actor(e1,x3) & v_float(e1) & (x2 = x3) & n_raft(x2) & n_girl(x1) & a_several(s1) & Theme(s1,x1))
exists e1 x1 x2.(n_girl(x1) & on(e1,x2) & n_hat(x2) & Actor(e1,x1) & v_have(e1))