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rank – v. give someone a position on a list of things in order of importance
impact – n. effect on something
habitat– n. the natural environment of an animal or plant
species – n. a group of animals or plants that are similar and can produce young animals or plants
extinct – adj. no longer existing in nature
drought – n. a period of extended dryness caused by a lack of rain
front lines – n. a position of direct and important influence
