a serious illness in which one or both lungs become red and swollen and filled with liquid

People who are bedridden can easily get pneumonia. 长期卧床的人易患肺炎。

to make yourself ill by getting too cold

She'll catch pneumonia going out without a coat in this weather! 她这种天气不穿大衣出去会得肺炎的！

Maybe he'll get soaking wet and catch pneumonia.

You'd probably catch pneumonia if you swam in this lake.

You'll get pneumonia if you stand around without any clothes on.

Let's go inside - we're in danger of getting pneumonia out here.