Question: How can a small stamp be worth $16,800? Any mistake made in the printing of a stamp raises its value to stamp collectors. A mistake on a two-penny stamp has made it worth a million and a half times its face value. Do you think it impossible? Well, it is true. And this is how it happened. The mistake was made more than a hundred years ago in the former British colony of M auritius , a small island in the Indian Ocean. In 1847 an order for stamps was sent to London. Mauritius was about to become the fourth country in the world to put out stamps. Before the order was filled and the stamps arrived from England, a big dance was planned by the commander-in-chief of all the armed forces on the island. The dance would be held in his house and letters of invitation would be sent to all the important people in Mauritius. Stamps were badly needed to post the letters. Therefore, an islander, who was a good printer, was told to copy the pattern of the stamps. He carelessly put the words "Post Office" instead of "Post Paid", two words seen on stamps at that time, on the several hundred that he printed. Today, there are only twenty-six of these misprinted stamps left--- fourteen One-penny Reds and twelve Two-penny Blues. Because there are so few Two-Penny Blues and because of their age, collectors have paid as much as $16,800 for one of them. When a mistake is made in the printing of the stamp, the stamp _ . A) will be thrown away B) increases in value C) is not worth buying D) is worth no more than its face value
Answer: B

Question: Do you like to sit in front of the computer and play computer games hour after hour? Have you ever thought of what that may be doing to your health? More and more children are becoming overweight and growing less creative because they spend too much time in front of the computer according to a survey. Last week Child Protective Services in America organized an activity. The aim of the activity was to encourage children to do some outdoor activities instead of playing computer games at home. Many American children spend about 1,000 hours a year playing computer games -- more time than they spend in school. As a result, they are overweight. Some of them have very poor _ , and they can't see clearly. Everyone should pay attention to his health and try to keep healthy. The doctor says that the longer children play computer games, the more overweight they may become. And the junk food children eat while they're playing computer games makes the weight problem more serious. To keep fit, children need to take exercise regularly, play outside with friends, and explore the world around them. Can you spend two weeks without playing computer games? It might be difficult for computer lovers, but why not have a try? Children may become _ if they play computer games all day. A) much younger B) much lighter C) less creative D) less careful
Answer: C

Question: Scientists think that many animals cannot see colours. The world is black and white to them. Scientists want to find out if dogs can see colours. When the scientists give the dogs food, they show them a certain colour every time. The dogs get ready to eat when they see this colour. The scientists then show the dogs another colour. Again the dogs get ready to eat. The colours are all the same to them. Colours are not all the same to monkeys. For example, if we put food in a red box, and do this every day, a monkey will always go to the red box to get food. If we put food in a blue box, the monkey won't go to it. Colours are _ . A) all the same to monkeys B) not all the same to dogs C) different to dogs D) not all the same to monkeys
Answer:
D