The water is very clear.
The water is clean and drinkable.
Just because water is clear does not mean that it is drinkable.
exists s1 x1.(n_water(x1) & r_very(s1) & Theme(s1,x1) & a_clear(s1))
exists s1 s2 x1.(n_water(x1) & Theme(s2,x1) & a_drinkable(s2) & Theme(s1,x1) & a_clean(s1))