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identical twin – n. either member of a pair of two babies that are produced from a single egg and who look exactly alike
hyperactivated – adj. made more active than is usual or desirable
alien – adj. not familiar or like other things you have known
congestion – n. a condition where a part of the body is blocked with fluid, such as blood or mucus
DNA (deoxyribonucleic acid) – n. a substance that carries genetic information in the cells of plants and animals
alert – n. the state of being ready for something you have been warned about, such as an attack
anticipate – v. to think of something that will or might happen in the future
expose – v. to cause someone to experience something or to be influenced or affected by something
mission – n. a flight by an aircraft or spacecraft to perform a specific task
