The key distinction between a duvet and comforter is that a comforter is only one piece of bedding while a duvet necessitates two individual pieces — an insert and cover. A usual quilting method for a comforter entails evenly distributing the filling, whereas, for a duvet, the fill goes inside the insert.
Scientists have yet to figure out why we yawn.
Although some studies suggest that we yawn to cool our brains down and keep the brain from clotting. Another reason suggests that it could be the body’s way of waking itself up. The motion from yawning also helps stretch the lungs and their tissues and allows the body to flex its joints and muscles.