TOEFL

obtain - come into possession of :: incur hold

irrigation - supplying dry land with water by means of ditches etc

intensify - increase in extent :: strengthen

nourish - provide with sustenance

fertilize - provide with fertilizers or add nutrients to

cultivation - production of food by preparing the land to grow crops :: polish

gather - assemble or get together

aggregate - a sum total of many heterogeneous things taken together :: collection blend combination mass mix

adversely - in an opposing manner

abandon - forsake, leave behind

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