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chest - n. the front part of the body between the neck and the stomach
tangle - n. a twisted knot of hair, thread or wires
congenital - adj. existing since birth
heart – n. the organ in your chest that pumps blood through your veins and arteries
surgery - n. medical treatment in which a doctor cuts into someone's body in order to repair or remove damaged or diseased parts
NGO - n. a non-governmental organization, such as a charity
