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artifact – n. a simple object made by people in the past
cave – n. a large hole that was formed by natural processes in the side of a cliff or hill or under the ground
incredible – adj. very good or exciting
incense – n. a substance that burns with a strong, sweet smell, often used in religious ceremonies
crawl – v. to move on your hands and knees
sinkhole – n. a hole in the ground, especially in an area of limestone rock, that has been formed naturally
