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index - n. a number that indicates changes in the level of something (such as a stock market) when it rises or falls
automatic - adj. always happening because of a rule, law, previous agreement, etc.
lock - v. to hold (someone or something) in a fixed position
nursing home - n. a place where people who are old or who are unable to take care of themselves can live and be taken care of
immunity - n. the power to keep yourself from being affected by a disease
response - n. something that is done as a reaction to something else
isolate - v. to put or keep (someone or something) in a place or situation that is separate from others
cruise - n. a journey on a boat or ship to a number of places as a vacation
quarantine - n. the situation of being kept away from others to prevent a disease from spreading
actual - adj. known to be correct or precise : not false or apparent
mask - n. a covering used over the mouth and nose to stop the spread of infection from one person to another
toy - n. something a child plays with
peak - v. the highest level or degree of something
generate - v. to produce (something) or cause (something) to be produced
absolutely - adv. completely or totally
