To demand is to request something in a strong way. A demand is that request, and someone described as demanding makes a lot of difficult requests.
Ex: My football coach had a list of demands we had to meet in order to stay on the team. They included curfews, bedtimes, and dietary restrictions.
Ex: Babies are very demanding. They demand to be fed, burped, and changed at frequent intervals around the clock. Parenting is not a part time job. If something is in demand, it is highly sought after. Supply and demand is an economic principle.
When something is in great demand, a business should increase its supply, or amount, of that item. Some items are in great demand because the supply is limited or it is rare.
Ex: When the price of gold went up dramatically, demand for gold jewelry declined. As a result, several stores offered big discounts to entice customers to buy their inventory.
Ex: Salt Lake City's population is increasing rapidly as more young families are moving there for career opportunities. Now single family homes are in great demand, and the average price for one in rising.
To control something is to have power over it, and control is the power to make decisions about the actions of someone or something. The person who does this is described as controlling.
Ex: I have little control over my appetite for chocolate. In fact, I think of brownies as one of the major food groups.
Ex: My mother controls what we eat, what we wear, and when we go to bed. To say that she's a controlling parent is an understatement.
The controls refers to the mechanics and instruments in the cockpit of a plane. If your little brother is out of control, he is acting impulsively and won't listen to your parents.
Ex: When Captain Smith is at the controls, the passengers on the plane are guaranteed a smooth ride and a soft landing. He loves to fly.
Ex: Molly's love of Taylor Swift's music is out of control. She has all Swift's songs on her iPod and travels great distances to attend her concerts.