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axis - n. the imaginary straight line that something (such as the Earth) turns around
briefcase - n. a flat case that is used for carrying papers or books
core - n. the central part of a fruit (such as an apple) that contains the seeds
curveball - n. a pitch that is thrown with spin so that the ball curves in the air
desk - n. a piece of furniture that is like a table and often has drawers
dig - v. to move soil, sand, snow, etc., in order to create a hole
geological - adj. a science that studies rocks, layers of soil, etc., in order to learn about the history of the Earth and its life
mission - n. a task or job that someone is given to do
spacecraft - n. a vehicle that is used for travel in outer space
vibration - n. a continuous slight shaking movement
