阅读理解。 What do people do with their old, out-of-date but still useful computers? Most people don't know what to do with them. Many old computers are put away in homes. Many more are simply thrown out with the rubbish.　　 Some companies are thinking of ways to bring down the number of old computers. Sony has agreed to help recycle old Sony products. Dell, Hewlett-Packard and other companies now also take back some old computers.　　      In some countries, laws are being passed, too. Computer companies will have to collect and recycle their used products. And 70% of computer waste must be recycled. The idea behind the laws is that computer companies themselves should pay the cost. That will encourage them to make computers that are easier and cheaper to repair and upgrade (升级). Yet while many people are throwing away good computers, others cannot afford them at all. Hundreds of organizations are working to solve this problem. They collect and repair old computers. Some also teach others how to repair computers. The computers then go to schools, charities and people who need them. Giving a used computer to one of these organizations can turn one person's rubbish into someone else's useful things-and cut down on waste, too. 1. How do people usually deal with their old computers? A. They stop using them. B. They give them to others. C. They fix them up. 2. What do some computer companies do to bring down the number of old computers? A. They don't do anything about them. B. They take back some old ones. C. They donate them to some charities 3. According to some countries' laws, what must computer companies do? A. Collect and recycle most of computer waste. B. Repair and upgrade old computers. C. Make much cheaper computers. 4. What may people who can't afford computers think of the used computers? A. Expensive. B. Useful. C. Out-of-date. 5. What is the passage about? A. Repairing old computers. B. Selling old computers. C. Recycling old computers.