Two young girls are enjoying riding down a hill in the snow.
the girls are sisters
Two girls playing together need not be sisters.
exists e1 p1 s1 x1 x3.(n_snow(x3) & exists e2 s2 x2.(in(e2,x3) & a_down(s2) & Manner(e2,s2) & Theme(e2,x2) & Actor(e2,x1) & v_ride(e2) & n_hill(x2)) & Topic(e1,p1) & Actor(e1,x1) & v_enjoy(e1) & n_girl(x1) & a_young(s1) & Theme(s1,x1) & card_eq_2(x1))
exists p1 x1.(n_girl(x1) & exists x2.((x1 = x2) & n_sister(x2)))