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skateboard - n. a short board that is on wheels and that a person stands on to move along a surface or to perform tricks
cast - n. a hard covering that is put on an arm, leg, etc., so that a broken bone can heal
defective - adj. having a problem or fault that prevents something from working correctly
submit - v. to give (a document, proposal, piece of writing, etc.) to someone so that it can be considered or approved
