a couple of people struggling through a muddy pit
They are swimming in the fish tank
The people can't be swimming while struggling through a pit.
exists e1 s1 x1 x2 x3 x4.(a_topic(x1) & through(e1,x4) & n_pit(x4) & a_muddy(s1) & Theme(s1,x4) & Actor(e1,x3) & v_struggle(e1) & (x1 = x3) & of(x1,x2) & n_people(x2) & n_couple(x1))
exists e1 x1 x2 x3.(n_tank(x2) & of(x2,x3) & n_fish(x3) & n_thing(x1) & in(e1,x2) & Actor(e1,x1) & v_swim(e1))