a person standing in the middle of a bunch of snowy rocks near a waterhole.
A person is ice fishing in the snow, while perched on a rock
The person is standing in the middle of rocks, not perched on one and being near the waterhole doesn't indicate the person is fishing.
exists s1 x1 x2 x3 x4 x5 x6.(n_middle(x3) & a_topic(x1) & in(x1,x3) & of(x3,x4) & near(x4,x6) & n_waterhole(x6) & of(x4,x5) & n_rock(x5) & a_snowy(s1) & Theme(s1,x5) & n_bunch(x4) & n_standing(x1) & of(x1,x2) & n_person(x2))
exists p1 x1 x2 x3 x4.(n_snow(x2) & on(p1,x4) & n_rock(x4) & while(p1,x3) & n_perch(x3) & in(p1,x2) & exists x5 x6.((x1 = x5) & n_fishing(x5) & of(x5,x6) & n_ice(x6)) & n_person(x1))