a young girl wearing a gray snowsuit skiing on a snowy mountain.
Nobody is skiing
One claims a young girl while the other claims nobody, these are not the same.
exists e1 s1 s2 s3 x1 x2 x3 x4 x5.(a_topic(x1) & Theme(e1,x3) & Actor(e1,x2) & v_wear(e1) & on(x3,x5) & n_mountain(x5) & a_snowy(s3) & Theme(s3,x5) & n_skiing(x3) & of(x3,x4) & n_snowsuit(x4) & a_gray(s2) & Theme(s2,x3) & (x1 = x2) & n_girl(x1) & a_young(s1) & Theme(s1,x1))
-exists p1 x1.(exists x2.((x1 = x2) & n_skiing(x2)) & n_person(x1))