The water is very calm.
The water is calm because it is an indoor pool.
Not all water is an indoor pool.
exists s1 x1.(n_water(x1) & r_very(s1) & Theme(s1,x1) & a_calm(s1))
exists p1 s1 x1.(n_thing(x1) & n_water(x1) & exists p2 s2 x2.((x1 = x2) & n_pool(x2) & a_indoor(s2) & Theme(s2,x2)) & because(s1,p1) & Theme(s1,x1) & a_calm(s1))