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pledge – v. to formally promise to give or do (something)
absent – adj. not present at a usual or expected place
greenhouse gas – n. carbon dioxide and other gases that scientists have linked to rising temperatures in Earth’s atmosphere
renewable energies – n. any naturally occurring source of energy like solar, wind, biomass, tidal and hydroelectric power that is not taken from nuclear or fossil fuel.
emission – n. the act of producing or sending out something (such as energy or gas) from a source
stand in the gap – expression to take the place of a person who has fallen (sometimes a religious expression)
commercialization – n. to make something available to customers
looms – v. hangs over
enact – v. to make (a bill or other legislation) officially become part of the law
courageous – adj. very brave : having or showing courage
