Tap water 自来水
Running water 自来水
People there don’t drink tap water because it’s not fresh.
Be in hot water 惹上麻烦
I was in hot water last night when Penny found out I went to the movies instead of cleaning out the garage.
Make one's mouth water
The smell of the grilled chicken made my mouth water.
Pour/throw cold water on sth.泼冷水
I have lots of ideas about how to improve sales but my manager pours cold water on all of my suggestions.
Water under the bridge
That argument we had is just water under the bridge now—don't even worry about it.