This document defines and provides examples for several key vocabulary words: dancer, electricity, enthusiasm, expert, and pupil. It explains that a dancer leads balls because she is an excellent dancer. Electricity is produced from nuclear energy and powers things. Enthusiasm means passion and excitement, as shown by a boy's enthusiasm for baseball. An expert is very knowledgeable in a subject, like expert drivers. A pupil is a student, whether putting effort into a problem or having their own desk.