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front line(s) – n. the most important and active position in a job or field of activity
essential – adj. extremely important and necessary
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
invisible – adj. impossible to see
delivery – n. the act of taking something to a person or place
tendon – n. a tough piece of tissue in your body that connects a muscle to a bone
customer(s) – n. someone who buys goods or services from a business
insurance – n. an agreement in which a person makes regular payments to a company and the company promises to pay money if the person is injured or dies, or to pay money equal to the value of something (such as a house or car) if it is damaged, lost, or stolen
quarantine(d) – v. to keep (a person or animal) away from others to prevent a disease from spreading
anxiety – n. fear or nervousness about what might happen
pistol(s) – n. a small gun made to be aimed and fired with one hand
