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apply - v. to have an effect on someone or something
challenge - n. something that is hard to do
elder - n. a person who has authority because of age and experience
instruct - v. to teach (someone) a subject, skill, etc.
psychologist - n. a scientist who specializes in the study and treatment of the mind and behavior
subsistence - adj. where people produce food to eat themselves rather than to sell.
tobacco - n. a plant that produces leaves which are smoked in cigarettes, pipes, etc.
