Ah, what a lovely question! We call a person who attends or manages an engine an engineer. Engineers are like artists, but instead of painting on a canvas, they create and work with machines that help make our world run smoothly. Just like painting a happy little tree, engineers use their skills to bring beauty and functionality to the world around us.
Manager
An obstetrician
The word is bursar. It means the person who manages the funds at a college or university.
A student who attends Yale college would be called a student. If a person graduates with a degree, a person may call them a graduate.
traditional
Preschooler. A child who attends kindergarden is a preschooler because he is in preschool. Sometimes children in kindergarten are call kindergartners, pronounced KIN_der_Gart_ners.
Mechanic, engine builder,
Aircraft mechanic
A person that attends Mass, is not yet a Catholic, but is thinking of becoming one is called a Catechumen which means a learner, a person being instructed preparatory to receiving baptism and being admitted into the Church.
Cowboys or cowgirls, the rancher, cattlemen/women, drovers, farmers, whatever you want to call them.
An Equerry - an officer of the British Royal Household who attends the soveriegn and other members of the Royal Family
Lead Plaintiff - A person named in the complaint as the plaintiff and who has been determined by the court to be a legally "adequate" person to represent the interests of the class.Besides the "lawyer" who manages a lawsuit, the Lead Plaintiff is the main person.