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juice – n. the liquid part that can be squeezed out of vegetables and fruits
contributor – n. someone or something that contributes something or that contributes to something
factor – n. something that helps produce or influence a result: one of the things that cause something to happen
adolescent – n. a young person who is developing into an adult : a young person who is going through adolescence
tripled – v. to cause (something) to become three times as great or as many
challenge – n. a difficult task or problem: something that is hard to do
