All of us use energy every day - for transportation, (21) , heating and cooling rooms, manufacturing, lighting, and entertainment. The choices we make about how we use energy - turning machines off (22) we’re not using them or choosing to buy energy efficient appliances - impact our environment and our lives.
There are many things we can do to use less energy and use it more wisely. Two main ways to (23) energy are energy conservation and energy efficiency. Turning the light (24) when you leave the room and recycling aluminum cans are both ways of conserving energy. Energy efficiency is the use of technology that requires less energy to perform the same function. A compact fluorescent light bulb that uses less energy than (25) ordinary bulb to produce the same amount of light is an example of energy efficiency.

When another old cave is discovered in the south of France, it is not usually news. Rather, it is an ordinary event. Such discoveries are so frequent these days that hardly anybody pays heed to them.
However, when the Lascaux cave complex was discovered in 1940, the world was amazed. Painted directly on its walls were hundreds of scenes showing how people lived thousands of years ago. The scenes show people hunting animals, such as bison or wild cats. Other images depict birds and, most noticeably, horses, which appear in more than 300 wall images, by far outnumbering all other animals.
Early artists drawing these animals accomplished a monumental and difficult task. They did not limit themselves to the easily accessible walls but earned their painting materials to spaces that required climbing steep walls or crawling into narrow passages in the Lascaux complex. Unfortunately, the paintings have been exposed to the destructive action of water and temperature changes, which easily wear the images away. Because the Lascaux caves have many entrances, air movement has also damaged the images inside. Although they are not out in the open air, where natural light would have destroyed them long ago, many of the images have deteriorated and are barely recognizable. To prevent further damage, the site was closed to tourists in 1963, 23 years after it was discovered.