Pneumonia is a serious illness of the lungs. The tiny air sacs become inflamed — swollen and sore, often filling with fluid — so it is hard to breathe, and the body may not get enough air.

Pneumonia就是 is a serious illness of the lungs一種嚴重的肺部疾病。The tiny air sacs那些細小的氣囊 become inflamed — swollen and sore, often filling with fluid會發炎——腫脹、疼痛，常常還積滿液體——so it is hard to breathe所以會很難呼吸，and the body may not get enough air身體可能得不到足夠的氣。

People with pneumonia often have a bad cough, fever, chest pain, and a heavy, tired feeling. It can follow a cold or flu, or come from germs of its own.

People with pneumonia得pneumonia的人 often have常常會有 a bad cough, fever, chest pain, and a heavy, tired feeling很嚴重的咳嗽、發燒、胸痛，還有一種沉重、疲累的感覺。It它 can follow a cold or flu可能接在感冒或流感之後，or come from germs of its own也可能是自己的病菌造成的。

Young children and older people can become very sick; it is not 'just a cough', and doctors treat it as something that needs real care, sometimes in hospital.

Young children and older people小小孩和年紀大的人 can become very sick可能會病得很嚴重；it is not 'just a cough'它不只是「一個咳嗽」而已，and doctors treat it as something that needs real care, sometimes in hospital醫生會把它當成需要認真治療的病，有時候要住院。

It is a medical word, used by doctors and also by ordinary families when someone is that ill. You do not use it for a light cold.

It它 is a medical word是一個醫學用詞，used by doctors and also by ordinary families when someone is that ill醫生會用，一般家庭在有人病得那麼重的時候也會用。You do not use it for a light cold你不會拿它來講輕微的感冒咳嗽。