2009年6月大学英语四级考试备考模拟试题

　　26. Why was the hemp plant essential to world-wide trade in the past?

　　A) Because ships’ ropes were made from it.

　　B) Because hemp was a very profitable export

　　C)Because hemp was used as fuel for ships.

　　D)Because hemp was used as food for sailors.

　　27. Why do agriculturalists think that hemp would be better for paper production than trees?

　　A) Because it is cheaper to grow hemp than to cut down trees.

　　B) Because more paper can be produced from the same area of land.

　　C) Because hemp produces higher quality paper.

　　D) Because hemp can be made into paper, fuel, oils, textiles, food, and rope.

　　28.Why was hemp banned?

　　A) Because it was related to the marijuana plant.

　　B) Because it was illegal in many countries of the world.

　　C) Because it was no longer a useful crop.

　　D) Because it was destructive to the land.

　　29. According to the passage, which of the following statements is TRUE?

　　A) Fiber is a powerful chemical ingredient of the cannabis plants.

　　B) Some activists believe that both marijuana and hemp should be legal.

　　C) Canada has just legalized marijuana.

　　D) Hemp was illegal in George Washington’s and Thomas Jefferson’s time.

　　30. What is the main idea of the passage?

　　A) Hemp was essential to the economies of many countries.

　　B) Hemp is illegal in many countries.

　　C) Hemp plants are being legalized.

　　D) All of the above.

　　Part IV

　　Cloze

　　(15minutes)

　　Directions: There are 20 blanks in the following passage. For each blank there are four choices marked A), B), C) and D). You should choose the ONE that best fits into the passage.

　　What does Dyslexia(诵读困难症) have to do with food or nutrition? At the 56th Annual Conference of the International Dyslexia Association in Denver, Dr. Susan Koger, a professor from Willamette University in Oregon, presented a(n) 31 paper on the risks of environmental toxins(毒素)for developing learning differences, 32 dyslexia. Dr. Koger emphasized that humans are 33 during their lifetime to potential exposure 34 75,000 or more synthetic chemicals. More than 98 percent of families and 80 percent of pregnant women are 35 to these potential chemical toxins. The metabolites(代谢产物)or breakdown 36 of these chemicals can be identified in the urine(尿)of 82 percent of adults and 92 percent of children. Dr. Koger postulated that basically every human on the planet has detectable amounts of one or more of these toxins in their system 37 one time or another.

　　It is our food supply that is of particular 38 , because these bio-toxins become concentrated as they make their way up the food chain. For instance, 891 pesticides have been 39 and used since 1941. Of these, 523 have been used 40 on our food or on feed stored for animals. Of those that are used in our food supply, 140 are 41 neuro-toxic(毒害神经的)and can injure the brain. 42 , they were designed to kill insects and rodents. Only 12 of these 140 neurotoxins have been 43 for potential harm to the brain. No test for potential brain injury from these chemicals is 44 before they are released 45 use. The concern that Dr. Koger’s research 46 , by extrapolation(推断), is that perhaps the older teachers may 47 part have been right, that the frequency of dyslexia in the student population was indeed once only two or three per-cent. The frequency now 48 , which is real at 17 to 25 percent, may be a reflection of the increased potential for damage to the developing brain of the fetus or newborn infant or toddler, perhaps 49 extending into the first few years of life, 50 by the toxic chemicals we have put into our environment. That is a frightening consideration.