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artifact - n. a simple object (such as a tool or weapon) that was made by people in the past
drawing - n. a picture, image, etc., that is made by making lines on a surface with a pencil, pen, marker, chalk, etc., but usually not with paint
evolution - n. a theory that the differences between modern plants and animals are because of changes that happened by a natural process over a very long time
ladder - n. a device used for climbing that has two long pieces of wood, metal, or rope with a series of steps or rungs between them
species - n. a group of animals or plants that are similar and can produce young animals or plants
