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pill – n. a usually medicinal or dietary preparation in a small rounded mass to be swallowed whole
annually – adv. once a year : each year
expensive – adj. costing a lot of money
adherence – n. the act of doing what is required by
symptom – n. a change in the body or mind which indicates that a disease is present
variant – n. strains of a disease
challenging – adj. testing one's ability, endurance, etc:
