Helyes ez a mondat? (angol)

Nem, helyesen így lenne:

I warn you not to drink river water because it is undrinkable.

Elsőnek ment a zöld kéz, de én cifráznám:)

I warn you not to drink from the river because the water is undrinkable.

Amúgy, hová kell? Nem lenne egyszerűbb csak annyit írni, hogy: Don't drink from the river because...

undrinkable helyett, inkabb not safe/unsafe to drink.

I warn you/Warning. The water from the river is not safe to drink/is unsafe for human consumption.