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three-dimensional – adj. appearing to have length, depth and width
survey – n. an examination of an area in which its measurements and details are recorded, especially for the purpose of creating a map
galaxy – n. a large group of stars from the same universe
gap – n. an empty hole or space in the middle of something
substantial – adj. large in amount
advance – n. new discoveries and inventions
pattern – n. the way something is often done or repeated
legacy – n. something that is left for people in the future
