A man standing in the water at the base of a waterfall.
A man is sitting in the hot tub.
One cannot be simultaneously both standing and sitting. Also a waterfall is a different object (a natural feature) than a hot tub.
exists x1 x2 x3 x4 x5.(n_base(x4) & n_water(x3) & a_topic(x1) & in(x1,x3) & at(x3,x4) & of(x4,x5) & n_waterfall(x5) & n_standing(x1) & of(x1,x2) & n_man(x2))
exists e1 s1 x1 x2.(n_tub(x2) & a_hot(s1) & Theme(s1,x2) & in(e1,x2) & Actor(e1,x1) & v_sit(e1) & n_man(x1))