transition – n. a change from one state or condition to another

inauguration – n. an act or ceremony of introducing into office

challenge – n. an action, statement, etc., that is against something; a refusal to accept something as true, correct, or legal; also a difficult task or problem

certify – v. to say officially that something or someone has met certain standards or requirements

pandemic – n. an occurrence in which a disease spreads very quickly and affects a large number of people over a wide area or throughout the world
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