If you see a person carelessly throw a cigarette to the ground, what are you likely to think? That depends.If you hate people throwing things on the ground, you might think, "That person should not litter." If you are a smoker, you might think, "I would sure like a cigarette right now." Most likely, though, you are not thinking, "You know, that unused cigarette butt could be used to make something, something amazing!" That is, unless you are a creative scientist. If you are, you may see potential, a possibility where others simply see rubbish. That is just what has happened in South Korea.The spirit of invention can hit at the strangest times and in the most unusual places. Kim Gil-Pyo is with the Seoul National University. Mr. Kim says he saw people throwing away cigarette butts. And that got him thinking. He began wondering if something useful could be made from them, The result? Mr. Kim and other researchers found a way to change cigarette butts into the materials required for high-performance batteries.Kim Gil-Pyo says he and his fellow researchers looked closely at used cigarette filters. The filter is the part of the cigarette that smokers put into their mouths. Filters are made of a material called "cellulose acetate."Mr. Kim explains that cellulose acetate can be made into another material: He says the pieces of cellulose acetate, known as fibers, are changed through a one-step burning process. After this, he says, they are converted into an energy storage material.But why use carbon? Carbon has many qualities that seem to make it the perfect material. Carbon has a high surface area. It conducts electricity well. In other words, carbon can easily carry an electrical current. It also stays stable, unlikely to change, for a long time. And carbon does not cost a lot. All these qualities make it the most popular material for making super-batteries, which are good at storing energy and require only a short time for recharging. Besides, they have a long lifecycle. Super-batteries are used in products such as laptop computers and cell phones. They are also used in industrial energy converters, like wind turbine machines. It really seems like a perfect marriage.Despite the fact, Kim Gil-Pyo tells the Reuters News Agency, that the idea hasn't aroused the interest of investors and it still needs improving, cigarette butts could affect the economy in a huge way and prove to be a low-cost source of carbon material. They are so cheap that smokers throw them to the ground. And you don't get much cheaper than that.1The passage is mainly intended to __________ .A. inform people of a new inventionB. predict the future of super-batteriesC. explain the function of cigarette buttsD. urge people to protect the environment2What's the main idea of Para. 3? A. Why Mr. Kim takes advantage of cigarette butts.B. How Mr. Kim is inspired to recycle cigarette butts.C. The phenomenon of throwing away cigarette butts.D. The way Mr. Kim invents highly-efficient batteries.3What is Kim Gil-Pyo's attitude towards the future of the naw invention? A. Uncertain.B. Optimistic.C. Concerned.D. Doubtful.4Which of the following can be used to summarize the passage? A. Every dog has his day.B. Experience must be bought.C. One man's trash is another man's treasure.D. Count your chickens before they are hatched.