(1) When the diaphragm contracts, the upper and lower diameters of the thoracic cavity increase and the lungs expand accordingly. At this time, the outside air enters the lungs, which is an inhalation process. When the rubber membrane D is pulled down by hand, the contraction of the diaphragm is simulated, so the balloon B will expand, indicating the inhalation process. (2) When inhaling, the intercostal muscle and diaphragm contract, so that the chest cavity is enlarged up and down, and the lungs will expand accordingly, so that the air pressure in the lungs is lower than the external atmospheric pressure, and the external air enters the lungs to form inhalation movement. When the air pressure in the lungs is equal to the external atmospheric pressure, the inhalation ends; When the external intercostal muscle and diaphragm relax, the diaphragm top rises, and the ribs and sternum return to their original positions due to their own gravity and elasticity. Therefore, the chest cavity contracts, and the lungs also contract, resulting in the air pressure in the lungs being higher than the external atmospheric pressure, which leads to expiratory movement. When the air pressure in the lungs is equal to the outside atmospheric pressure, the expiration ends. Therefore, at the moment when inhalation or exhalation ends, the air pressure in the lungs is equal to atmospheric pressure. (3) When inhaling, the outside air enters the lungs through the respiratory tract.
So the answer is: (1) expansion; Inhale (2)=(3) pharynx; Throat; Trachea; bronchus