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Text 4 A pure virus (病毒) could be kept in a bottle, just like hundreds of other chemicals. Yet, when a virus is placed on a living thing, it comes to life. As long as it is on a living material, it grows. A difficult question still remains - what is a virus Is it living or chemical Men of science had always thought life and not-life to be as different as black and white. With the discovery of the virus, they became aware of a grey area that was neither black nor white. Until the 1930’s, it was accepted that there was also a great difference in size between the largest chemical molecules (分子) and the smallest living things. As new and much finer filters (过滤器) were invented, men were able to measure viruses. The first virus to be measured was found to be about 100 millimicrons (毫微米) across. The largest known chemical molecule measures only 22 millimicrons. The smallest living thing measures almost seven times that size or 150 millimicrons. When viruses were measured, they were found to range in size from 16 millimicrons to 300 millimicrons. Most were found to be larger than the largest chemical molecules and smaller than the smallest living things. The answer to the puzzle - what is a virus - must be that it is both living and not living. In a living cell, it is a live thing. In a bottle, it is nothing more than a chemical. We now realize that the virus is actually a link between life and not-life. What is this text mainly about（）
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ext 1 Jumanji is a story for children about a very strange game - a game that becomes far too real and frightening for the players. It was a story by Chris Van Allsburg, which was later filmed in 1996, starring the famous American actor Robin Williams. The story begins in 1869 in New Hampshire, America. Two young brothers bury a box under some trees. A hundred years later, in 1969, a boy, Alan Panish, finds the box and takes it home. He’s unhappy that his father may want to send him to a boarding school (寄宿学校）. Alan’s friend Sarah arrives, and they open the box. Inside is a board game. At the start of the game, some words appear: “Do you want to leave the world behind and go back to the past Then this is the game for you.” Suddenly Alan finds that he is disappearing into the game. The story has a deep meaning. Through his adventures Alan learns something important - if you confront(面对) your fears, your problems will go away. Alan turns to face Van Pelt, the hunter who is trying to kill him. In doing so, he completes the game and returns to reality. Then he finds that his father is not going to send him to boarding school after all. In Jumanji, time is “elastic”. The film director Stephen Spielberg’s “Back to the Future” films play with time in the same way. Top scientists even tell us now that time travel is theoretically(理论上) possible! From the story we learn that Alan is a boy who （）
超显性学说只考虑了基因的显性效应。
Text 3 When Tom Szaky sees a juice container thrown away, he doesn’t see rubbish; he sees a pencil case. Sweet wrappers (包装纸) A beautiful kite. But these are not the imaginings of a dreamer. For the 28-year-old CEO of Trenton, New Jersey-based TerraCycle, they’re a business model. The fast-talking Szaky is leading the new industry of upcycling. Instead of recycling (shredding or breaking down materials and enabling them to be reproduced as other products), TerraCycle takes packaging headed for landfills (垃圾填埋) and reuses it - more or less whole. TerraCycle’s 85 employees make nearly 200 products, sold at shops such as Petco, Kmart, Whole Foods Market, and Target. Szaky’s $7.4 million company, now also moving ahead in Mexico, Canada, the United Kingdom and Brazil is a far cry from the business he founded with classmate Jon Beyer in 2002 as a freshman at Princeton University. The two entered a business competition with a plan to sell an organic plant fertilizer () made from worm waste. They lost the competition but started the business anyway. With their goal - to make products entirely out of rubbish - suddenly clear, Szaky knew the time was right to drop out of Princeton. TerraCycle’s first product used dining-hall waste to feed the worms and thrown-away bottles to package the fertilizer. The result: a cheap, green breakthrough. Word spread, and in 2004, Home Depot began carrying the fertilizer in its Canadian stores. To Szaky, waste does not exist in nature. TerraCycle is a “second chance” employer of, say, a piece of furniture, an ice-cream container. As Szaky points out: “The biggest problem with most green, fair-trade, and organic products is that they tend to cost more. At TerraCycle, everything is made from rubbish, and rubbish is free. People should be able to protect the planet without having to pay a cost for that right.” Who is Tom Szaky（）
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