Front vowels are produced with the tongue close to the front of the mouth (often called bright vowels).

Central vowels are produced with the tongue in a neutral middle position.

Back vowels use the back of the tongue, often called dark vowels.

Close vowels are made with the tongue near the roof of the mouth.

Close-mid vowels are about one third open between close and open.

Open-mid vowels are about one third from open to close.

Open vowels are made with the tongue as low as possible in the mouth.