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experiment - n. a test or trial carried out to prove if an idea is true or false, or to discover something
test - v. to attempt to learn or prove what something is like or how it will act by studying or doing; n. an attempt to learn or prove what something is like or how it will act by studying or doing; a group of questions or problems used to find out a person’s knowledge
extend - v. to stretch out in area or length; to continue for a longer time
infected - v. to make sick with something that causes disease
