World Asthma Day is on the first Saturday of May, it is a day to call for the public and the patients to pay attention to asthma and master more information of this sickness, so as to make better precaution. Nowadays, the problem of pollution has become serious. In some areas, the nature punishes people by bringing the bad weather, such as the great haze, which damages people’s health badly. Many children can’t breath well and they get sick easily. The polluted air makes them suffer from asthma. If people know more about the disease, they can take care of children well and make some action to prevent the infection. The key to prevent the disease is to protect the environment, at the same time, we need to take regular exercise.