一、完形填空。（每题1分，共10分）
Fire can help people in many ways. But it can also be very harmful(有害的). Fire can keep your house__①__, give light and cook food. But fire can burn things __②__. Big fire can burn trees, houses, animals or people.
Nobody knows how people began to use fire. But there are _③_ interesting old stories about how a man or woman started a fire. One is _④_ a man. The man __⑤__a very long time ago. He went up the sun and __⑥__ fire down.
Today people know how to make a fire with matches(火柴). Children sometimes _⑦_ to play with them. But matches can be very dangerous. One match can burn a piece of paper, and __⑧__it could burn a house. A small fire can turn into a big fire very quickly. So you _⑨_ be careful with matches.
Be careful with fire, and it will _⑩_you. But if you are not careful with fire, it may hurt you.
