San Diego County Office of Education

Pneumonia is too much mucus in the lungs. Mucus is the thick, sticky stuff found in your nose and lungs. You may cough up mucus when you are sick. Humans have two lungs that are used for breathing. Lungs are like balloons. As you breath, air comes in and goes out. If a lung gets filled with thick mucus, it’s hard to fill it with air. That’s pneumonia. ................
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