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sustainable - adj. involving methods that do not completely use up or destroy natural resources
density - n. the amount of something in a particular space or area
alleviation - n. the process of reducing the pain or trouble of (something) : to make (something) less painful, difficult, or severe
bare - adj. not covered by leaves, grass, trees, or plants
insurance - n. protection from bad things that may happen in the future — usually + against
distinguish - v. to notice or recognize a difference between people or things
scary - adj. causing fear
thatched - adj. made of dried plant material (such as straw or leaves)
roof - n. the cover or top of a building, vehicle, etc.
