Although in-flight infections thrive in dry environments like airplanes, your risk of getting sick from an airplane is actually low because of the air filters used.
2019年12月四級真題(第三套)閱讀 Section A
柯林斯高階英漢雙解學習詞典釋義
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過濾
To filter a substance means to pass it through a device which is designed to remove certain particles contained in it.