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recycle –v. to reuse something that has been used before often in another way
strain – n. a type of disease or plant
enzyme – n. a chemical substance produced by living cells that makes particular chemical reactions happen in animals and plants
fungus– n. a type of plant without leaves that gets its food from other living or decaying things
ecosystem – n. a biological community of interacting organisms and their physical environment
drastic – adj. sudden or extreme
