Say you’re sitting around with some friends playing video games and someone mentions a game that happens to be one of your favorites. “Oh, that game’s easy. So not worth the time,” one of your friends says. The others agree. Although you enjoy the game quite a lot, not wanting to argue with them, you go along with the crowd.

You have just experienced what is commonly referred to as peer (同伴) pressure, also called peer influence. You will adopt a certain type of behavior, dress, or attitude in order to be accepted as part of a group of your “peers”. As a teen, you are likely to have experienced the effect of peer pressure in a number of different areas.

We are all influenced by our peers at any age. For teens, as school and other activities take you away from home, you may spend more time with your friends than with your family. As you become more independent, your peers naturally play a greater role in your life.

According to Dr. Casey from Cornell University, teens are very quick and accurate in making decisions on their own and in situations where they have time to think. However, when they make decisions in the heat of the moment or in social situations, their decisions are often influenced by factors like peers. In a recent study, teen volunteers played a video driving game, either alone or with friends watching. The researchers discovered that the number of risks teens took more than doubled when their friends were watching, compared with when they played alone. This shows that teens may find it more difficult to control risky behavior when their friends are around, or in situations where they are extremely angry.

Just as people can influence us to make unwise choices, they can also influence us to make good ones. A teen might join in a volunteer project because his or her friends are doing it, or get good grades because his or her friends think getting good grades is important. In fact, friends often encourage each other to study, or try out for sports.

While we are always influenced by those around us, the decision to act or not is up to us. So, when it comes to decision making, the choice is up to you.

When you do some running, you have a lot of energy which comes from the movement of your body. When you suddenly stop, your body loses this energy. We already have watches and small medical devises (设备) which can use energy that we make when we move. In the future, people like police officers and soldiers may wear devices on their legs to “catch” this lost energy and keep it in batteries (电池). They could use the power for computers, radios or other devices.

In December 2008, most people walking across Hachiko Square, Tokyo, probably did not notice four yellow squares on the road as they hurried to work. The squares were made of special materials that make electricity when they change shape. When people stood on the squares, the shape of the materials changed and they produced electricity. The squares were only there for twenty days, but in that time they produced enough power to make a TV work 1,400 hours! Imagine putting these squares under all the streets in Tokyo. One day, we may turn our streets into power stations!

We can also use body heat. Every day, 250,000 people use Stockholm’s Central Station. They eat and drink, carry heavy bags, and run to catch trains—and their bodies produce a lot of heat when they do these things. Inside the station, the heat is taken from the air and used to heat water for a nearby building.

It is a great way to get free energy—all you need is a lot of people.