Original: During swallowing , the backward motion of the tongue forces the epiglottis over the glottus ' opening to prevent swallowed material from entering the larynx which leads to the lungs ; the larynx is also pulled upwards to assist this process .
Simplified: During swallowing , the backward motion of the tongue forces the epiglottis over the laryngeal opening to prevent swallowed material from entering the lungs ; the larynx is also pulled upwards to assist this process .