This compound contains a sulfhydryl group.

The aquifer in this area provides a very abundant water source.

My favorite classic novel is Water Margin.

Groundwater pollution has become a serious environmental problem.

I saw various aquatic creatures at the aquarium.

Before starting a new business, he said, 'Nothing ventured, nothing gained.'

He crossed many mountains and rivers to meet her.

He cautioned not to speak ill of others, saying, 'Illness enters by the mouth, and disaster does not come out of it.'

Please remember this old proverb, 'The friendship of a gentleman is insipid as water.'