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reserve – n. an area of land where animals and plants are given special protection
drought – n. a long period of time during which there is very little or no rain
distribution – n. the act of giving or delivering something to people
plain(s) – n. a large area of flat land without trees
take its course – expr. to permit something to happen without trying to control it
ecosystem – n. everything that exists in a given environment
stave off – p.v. to keep someone or something away usually for a short time
