Q: Do you know why you sleep? You may think it's because you're tired. Or perhaps you've been told sleep is good for you. Yet no one knows exactly why or how people sleep. Until the early 1950s, most scientists thought the body and brain rested during sleep. Then a scientist watched people sleep. He noticed that during periods of between 5 and 30 minutes each, sleepers' eyes made rapid movements, as if they were watching something. He called these periods REM sleep, for Rapid Eye Movement. Periods when sleepers' eyes did not move he called non-REM sleep. Whenever the scientist woke people during REM sleep, they were having vivid dreams. Measurements showed that sleepers' pulses went up quickly during REM sleep. Their breathing, heartbeat, and the blood going to the brain also increased. Far from being a time of rest, REM sleep is a time when the body is hard at work. Scientists still don't know the reason for this. Some believe REM sleep makes learning easier. Babies spend a lot of time in REM sleep. Because of this, some scientists believe that REM sleep helps the brain grow. Others think REM sleep is a time for the brain to empty the day's garbage. One thing all the scientists agree on is that sleep is necessary. Without enough sleep, people make mistakes. Most major car accidents happen during the early morning hours, when people are sleepiest. You can decide from the article that REM sleep _ . A) has a restful effect on people B) can be avoided with lots of sleep C) is something that all people experience D) is something that all scientists agree on
A: A

Q: One day Tom borrowed a pot from his neighbour, Ali. The next day he brought it back with another little pot inside. "That's not mine," said Ali. "Yes, it is." said Tom, "While your pot was staying with me, it had a baby." Some time later, Tom asked Ali to lend him a pot again. Ali said yes, hoping that he would once again get two pots in return. However, days passed and Tom still did not give the pot back. Finally Ali was angry and went to ask for it. "I am sorry," said Tom, "I can't give it back to you because it died." "Died!" cried Ali, "How can a pot die?" "Well," said Tom, "you believed me when I told you that your pot had a baby." Why was the neighbor happy to lend his pot a second time? A) Because he wanted to get more. B) Because he was a good neighbour. C) Because he had lots of pots. D) Because he likes to help others.
A: A

Q: "Tom? Are you in bed yet?" called Mrs White. There was no answer. Mrs White put down her book and went to her 14-year-old son's room. Tom was sitting in front of a bright computer screen on which a colourful dragon jumped and shouted. "Oh, Tom! You're still playing on that computer. You must stop now. It's half past eleven. If you don't go to bed soon, you'll be very tired tomorrow," said Mrs White. "But I've nearly beaten the dragon," said Tom. Mrs White could see the excitement on her son's face. She sat down beside him. "You are always playing on that computer. You spend more time with this machine than with your family," she said with a smile. "What's special about it? Show me what it can do!" "I think this is a great computer, Mum!" he said happily. "The hardware is good. There's so much memory and it has some wonderful software programs. This game, 'Dragon Player', is my favourite, but I sometimes borrow games from Daniel and other friends. I don't have to worry about any infected disks because I have a virus detector which can go over any disk and check it for viruses. Let me show you!" Tom began tapping. The screen changed in answer to his orders. "Oh, Tom," laughed Mrs White. "I'm sure it's a wonderful computer, but I'm afraid I don't know what you're talking about." Tom was excited because _ . A) the computer has a good memory B) the hardware is good C) he had nearly won the game D) his mother came to see him
A: C

Q: For a long time being happy was considered something that just happened, and there was nothing special about it. Now we know that getting along with other people is something that we can work at. It is possible to act in such a way that other people will like us better. One way is being unselfish, not wanting everything from our friends. Another way is to look for good points, not bad points in other people. It is surprising how successful this treasure hunt can be. You do not have to be spineless in order to be popular. In fact, you will be liked or loved if you are not afraid to stand up for your rights . But do it politely and pleasantly. Being friendly and polite to your group, to other people and to strangers and especially to those who do not look important or do not interest you is one way to develop a good character. You cannot expect to be perfect, and you must learn not to be unhappy when you make mistakes. Everyone makes mistakes, and no one is to be blamed if he does not refuse to learn from them. Many young people become discouraged when they know in themselves qualities that they do not like--selfishness, laziness, and other unpleasant qualities. Just remember that we all have some of these faults and have to fight against them. At the same time, it is important to remember that while you are probably no worse than others, the best way to be happy is to think yourself above other people. When something is wrong, it is good sense to try to make it right. Perhaps you do not like a teacher or a classmate. Try to see why, and look at yourself, too, to be sure that you are not doing anything to make that person dislike you. Some day, things may turn out all right when you have to learn to get along the best with the situation, without thinking too much about it. Worrying never helps in a situation you cannot change. One of the two ways the writer suggests for us to get along with others is to _ . A) work hard at everything we do B) enjoy the best share of everything C) look for treasure in order to be successful D) pay more attention to their strong points
A: D