What run but never walks, has a mouth but never talks has a bed but never sleeps?

A river. People describe a river as "running water". The mouth is the opening or beginning, and the riverbed is the shore.

Nice riddle.

Ooh I LOVE riddles.

The answer is a River.

A river is not only running water, but it also has a 'mouth' and riverbed.

A riverbed is the ground of the river, where it runs and flows through.

A river mouth is where it connects to another river, a lake, or even the ocean.