听力原文：This is our last meeting before the camps arrive tomorrow. I'll give u the activi

ty schedule later. But, now I want to answer a question one of u asked me yesterday about camps with asthma. Let me explain a little about the disease. First of all, it's chronical and very common. 20 million people in the United States alone have it. It affects the bronchial tubes that are the airways of the lungs. During normal breathing, air is drawn in through the mouse and nose, and eventually makes its way into the bronchial tubes. The asthma patient's bronchial tubes are very sensitive, and easily irritated by exercises or strength, exposure to allergy or pollution, or breathing in cold air, cigarettes smoke. When asthmatic suffers an attack, the airway path was constricted, making it difficult for the person from breathing normally. If a camp in your group has even a mild asthma, you would be informed and given further instruction about what to do in case of an attack. But don't worry. Some of our camps might have a mild case, but they always bring their medicines with them and we never have a problem. Are there any other questions？ Ok, let's talk about the schedule for tomorrow.

(40)

A．The diagnosis of asthma.

B．How to prevent an asthma attack.

C．What asthma is and what happens during an asthma attack.

D．The types of medicine available to an asthmatic.