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skull – n. the structure of bones that form the head and face of a person or animal
glucose – n. a type of sugar that is found in plants and fruits
high frequency – n. a radio frequency between very high frequency and medium frequency
ultrasound medical noun : a method of producing images of the inside of the body by using a machine that produces sound waves which are too high to be heard
inject – v. to force a liquid medicine or drug into someone or something by using a special needle — often + into
bubble – n. a tiny, round ball of air or gas inside a liquid
vibrate – v. to move back and forth or from side to side with very short, quick movements
a lot riding on (something) – phrase to be depending on the successful outcome or development of something
beam – n. a line of energy, particles, etc., that cannot be seen
steer – v. to control the direction in which something (such as a ship, car, or airplane) moves
