A group of people sitting by a lake.
A family is camped by a pristine lake.
The water in the lake could be murky and dirty and is not actually pristine.
exists e1 x1 x2 x3 x4.(a_topic(x1) & of(x1,x2) & by(e1,x4) & n_lake(x4) & Actor(e1,x3) & v_sit(e1) & (x2 = x3) & n_people(x2) & n_group(x1))
exists e1 s1 x1 x2.(Actor(e1,x2) & n_lake(x2) & a_pristine(s1) & Theme(s1,x2) & Theme(e1,x1) & v_camp(e1) & n_family(x1))