ABSTRACT
In all human languages most speech sounds are produced by pushing air out of the lungs, through the Glottis or voice box, and then through either the mouth or the nose. The glottis contains the vocal cords or folds, which if held together not too tightly as the air passes through them, will vibrate, giving rise to voicing. These vibrations can be felt by holding your Adam’s apple between your thumb and first finger, and making the sounds mm and aa. Speech sounds that are accompanied by voicing are said to be Voiced; all others are Voiceless. The mouth and nose cavities also have an important role: by modifying the stream of air passing through in various ways, production of a range of different sounds is possible.
