A Bright Idea
Evans Wadongo was from a village of Africa. He had to do homework by the light of a kerosene lamp（煤油灯）. Evans' eyes hurt and this made studying difficult. It was common in his village. Many children left school for this reason, so they remained poor for the rest of their lives.
Although studying was difficult, Evans was an excellent student and went to a university. He continued to worry about the kerosene lamp. By this time, he realized it was not just bad for schoolchildren but for the whole family. First, it can cause illnesses such as coughs. Also, the light can hurt people's eyes. Besides, it can lead to fires. Lastly, kerosene is expensive, so families have less money for food. It was difficult to come up with a different kind of lamp that was cheap and good for the environment. Yet Evans did not give up.
One day, he had an idea. He could use a small solar（太阳能的）light. Sunlight is free and solar power is good for the environment. Evans built his first solar lamp, and it worked. He began to build more lamps and sent them to local families. An organization heard about this and provided money for him to build more solar lamps.
Each lamp only cost $20. However, this was a lot of money to many villagers, who only earned around $34 a week, so Evans made sure he kept the cost down. First, Evans used recycled materials. Next, volunteers built the lamps. Finally, people from many countries gave away money to his team, so the lamps were usually free.
Thousands of people had safe light. Julia, a mother of three, said, "Thanks to Evans, my children have light to read, and I have my own light to cook. " The solar lamps made a big difference.
