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convalescent - adj. recovering from an illness
plasma - n. the watery part of blood that contains blood cells
illness - n. a condition of being unhealthy, sick
standard - n. a level quality or achievement that is considered acceptable
pandemic - n. an occurrence in which a disease spreads very quickly and affects a large number of people around the world
access - n. a way of getting something
evaluate - v. to judge the value or condition carefully
