You will be given a definition of a task first, then some input of the task.
In this task, you are given a paragraph, event and an entity. The event is part of the given paragraph and it changes the state of the entity. Your task is to classify the state of the entity into three classes: 1) not exist, 2) unknown location and 3) known location. "not exist" means the entity doesn't exist in that state anymore. "unknown location" means the entity exists in that state but location is unknown. "known location" means the entity exists and location is known. 

 "process paragraph : : You breathe air in. Air enters bronchial tubes. Air is then split into the bronchioles of each lung. Bronchioles have alveoli which are tiny air sacs. Alveoli is surrounded by many small blood vessels. Oxygen passes through alveoli into blood vessels. Blood leaves the lungs as it travels through the body. Blood carries carbon dioxide back to the lungs. Carbon dioxide released when you exhale. ", "event : Air enters bronchial tubes.", "entity : air" 
Output:
 known location 