Looking For Some Help

So i downloaded the Standard Assets and i wanna make it to where i it flows and looks like real life water but i go to the folder assets/environment/water/prefabs and i put the item into the map, after that i try to import the script into it but it says

"can't add script component 'water' because the script class cannot be found. Make sure that there are no compile errors and that the file name and class name match'

i really don't know what to do here.

Btw I'm importing the script "Water" not "waterbasic" or "watertile"

Any Help would be amazing