Why People Sneeze
A person sneezes to expel mucus which contains some irritants or foreign particles. When a person sneezes, the nasal cavity is cleansed. The ulva and soft palate get depressed whereas the back part of the tongue elevates, partially closing the mouth passages and allowing the air ejected from the lungs to be expelled through the nose. Since the mouth only closes partially, a significant amount of air is also expelled through the mouth. The extent of expulsion and the force of the air that travels through the nose vary.