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reverse – v. to change (something) to an opposite state or condition
scary as hell – phrase. very frightening (hell is the place where the devil lives, according to some religions
ecologist – n. a scientist who deals with relationships between groups of living things and their environments
Keeling Curve – n. a graph that shows the ongoing change in concentration of carbon dioxide in Earth’s atmosphere since the 1950s.
implication – n. what shows something or someone with close connections or involvement with something
arid – adj. have very little rain or water, very dry
flora – n. all the plants that live in a particular area, time, period, or environment
enhance – v. to increase or improve
