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pandemic– n. when a disease spreads quickly among a large number of people over a wide geographic area
sustainable– adj. able to be continued without causing severe problems or using up resources
outbreak– n. the sudden appearance of a disease or conflict
herd immunity– n. when a large part of a population cannot become infected with a disease because they have immunity to it
lockdown– n. a security measure of keeping prisoners in their cells; a situation when people are not permitted to go out for a safety-related reason
functioning– adj. to work or operate
