阅读理解。 How much sleep do we need? We are all different. Some people need only three hours of sleep a night. Others need ten hours of sleep a night. Most Americans sleep an average of seven to eight hours a night. After age fifty, the average sleep time goes down t0 6. 5 hours a night. Most people have a bad night when they cannot fall asleep. The name of this problem is called insomnia. This is not a new problem. Many famous people in history had insomnia. Some of these people had special ideas to make them sleep.  Benjamin Franklin, the famous statesman (政治家) and inventor, had four beds.  He moved from one to another to fall asleep. King Louis XI V of France had four hundred and thirteen beds and hoped to fall asleep in one of them. Mark Twain, the famous American writer, had a different way. He laid on his side across the end of his bed. 1. What does the sentence in the passage 'We are all different.' means? A. We don't look the same. B. No one looks like each other. C. We go to bed at different time. D. Our sleeping time is not the same. 2. In Chinese the word 'insomnia' means _____. 3. As people grow old, they need _____at night. A. more sleeping time B. no sleeping time C. less sleeping time D. a fixed time to sleep 4. People with the problem of insomnia _____. A. are too busy to sleep B. find it difficult to fall asleep C. find it hard to wake up in the morning D. have more beds 5. The best title for this passage may be _____. A. How to Solve the Sleeping Problem B. People and Sleep C. How Famous People Tried to Sleep D. People and Insomnia