托福听力每日一练lecture原文（第6天）_新东方网
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　　老托福听力是复习托福听力很有价值的材料，新东方网为同学们带来托福听力每日一练（共42天）的原文，同学们可以听写后对照原文，希望对同学们有所帮助。
　　托福听力每日一练第6天：（96年5月）
　　演讲听写训练1
　　At the beginning of the century the railroads were used to haul everything. Powerful railroad barons made fortunes without having to be accountable to the public or considerable to the customers. But cars and trucks changed all of that. And by 1970, the rail industry was beset with problems. Trucks were taking all the new business. And even so the rail industry remained indifferent to customers. Also many regulations kept the rail industry from adjusting to shifting market.& But in 1980, the rail industry entered the modern era when a deregulation bill was passed that allowed railroad companies to make quick adjustments to fees and practices. Companies reduced their lines by 1/3 and used fewer employees. They also took steps to minimize damage to product. And to increase their shipping capacity by stacking freight containers on railroad cars. To accommodate these taller loads, underpasses and tunnels were enlarged. The image of the rail industry has changed dramatically. Today companies are very responsive to customers and are gaining increasing market shares in the shipping industry. The railroad safety record is also strong. Freight trains have an accident rate that is only 1/3 that of the trucking industry.& Trains also come out ahead of the trucks on environmental grounds because they give off only 1/10 to 1/3 the pollution that is emitted by trucks. And railroading does not wear out highways as trucks do.
　　演讲听写训练 2
　　This coffee can contains soil from my garden. And I prepared slide samples to show you that it is alive. This ordinary backyard dirt is crawling with microbes.& Microbes is not a very specific term. There are hundreds of thousands of different species called microbes. What they have in common is that we can't see them with a naked eye. They are microscopic. Look at this slide. You should see some round cells. Those are yeasts . Yeasts are fermenters. And they are necessary for making bread, beer, yogurt and so forth. Now look for an irregular shape with hairs coming out of it. That's a mold.& Molds are decomposers, and they are responsible for the decomposition mycoplastlees. You should also see some protozoa. Some protozoa, like the one causes malaria are harmful to people.& A microbic that causes disease is called a pathogen. Finally you should see a lot of squiggly lines. They are bacteria. The oldest form of life on earth. Like these other microbes, bacteria are single-cells. But they are even simpler structurally because their cells do not have nuclear.& So I've got about a teaspoon of soil in my hand here. In that teaspoon are about ten thousand protozoa, 200 thousand mold cells, a million yeasts, and probably a billion bacteria.
　　演讲听写训练 3
　　Ten years ago the eccentric cyclist peddling furiously through the first snowstorm of the year was a rare sight often captured on film for the evening news? Today however it is estimated that four to five percent of cyclists bicycle year round. The increased popularity of winter cycling can be attributed to the creation of mountain bike and its subsequent imitations. Outfitted with parts more sturdy than those of yesterday, equipped with their more stable bicycles, nothing seems to stop the new breed of winter cyclist. With streets dry and clear on most winter days, many winter cyclists wear running shoes and protect themselves from cold by wearing down-hill-skiing clothes. On wet days cyclists can wear special water-proof boots over their shoes. But for all of its popularity, there is a down side to winter cycling. Even mountain bikes can't withstand winter snow and rain without extensive upkeep. But one bicycle store owner is in the final stages of developing a year-round bicycle with an innovated complete chain cover. With bicycle chains covered, cyclists would need to clean and oil their chains only once every six months instead of once a week. Despite her invention, however, she still advises cyclists to take a taxi or bus when it snowing heavily. Not because the conditions are too arduous for bicycles but because she believes bikers can't have confidence in the people who drive cars on days of reduced visibility.
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托福听力：新托福TPO（1-24）听力原文文本TPO17
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第6页：Lecture 4
　　TPO 17 Lecture 4　　Biology(Octopus)　　Narrator　　Listen to part of a lecture in a biology class.　　Professor 　　Ok, now I want to talk about an animal that has a fascinating set of defense mechanisms. And that's the octopus, one of the unusual creatures that live in the sea. 　　The octopus is prey to many species, including humans, so how does it escape its predators?　　Well, let me back up here a second. Anyone ever heard of Proteous? Proteus was a God in Greek mythology who could change form. He could make himself look like a lion or a stone or a tree, anything you wanted, and he could go through a whole series of changes very quickly. 　　Well, the octopus is the real world version of Proteus. Just like Proteus, the octopus can go through all kinds of incredible transformations. And it does this in three ways: by changing color, by changing its texture, and by changing its size and shape. 　　For me, the most fascinating transformation is when it changes its color. It's a normal skin color, the one it generally presents, is either red or brown or even grey, and it's speckled with dark spots. But when it wants to blend in with its environment to hide from its enemies, it can take on the color of its immediate surroundings: the ocean floor, a rock, a piece of coral, whatever. Charles?　　Student　　Do we know how that works, I mean, how they change colors?　　Professor　　Well, we know that the reaction that takes place is not chemical in nature. The color changes are executed by two different kinds of cells in the octopus' skin, mainly by color cells on the skin's surface call chromatophores　　Chromatophores consist of tiny sacks filled with color dye. There might be a couple hundred of these color sacks per square millimeter of the octopus' skin, and depending on the species, they can come in as many as five different colors. Each one of these sacks is controlled by muscles. If the muscles are relaxed, the sack shrinks, and all you see is a little white point. But if the muscle's contract, then the sack expands, and you can see the colors. And by expanding different combinations　　Student　　And just with various combinations of those five colors, they can recreate any color in their environment?　　Professor　　Well, they can no doubt create a lot with just those five colors, but you are right, maybe they can't mimic every color around them, so that's where the second kind of cell comes in. 　　Just below the chromatophores is a layer of cells that reflect light from the environment, and these cells help the octopus create a precise match with the colors that surround them. The colors from the color sacks are supplemented with colors that are reflected from the environment, and that's how they are able to mimic colors with such precision. So, that's how octopus mimic colors. 　　But they don't just mimic the colors
they can alos mimic the texture of objects in their environment. They have these little projections on their skin that allow them to resemble various textures. The projections are called papillae. If the octopus wants to have a rough texture, it raises the papillae. If it wants to have a smooth texture, it flattens out the papillae, so it can acquire a smooth texture to blend in with the sandy bottom of the sea. 　　So the octopus has the ability to mimic both the color and the texture of its environment. And it's truly amazing how well it can blend in with its surroundings.　　You can easily swim within a few feet of an octopus and never see it.　　Student　　I read that they often hide from predators by squirting out a cloud of ink, or something like that.　　Professor　　Yes. The octopus can release a cloud of ink if it feels threatened. But it doesn't hide behind it, as is generally believed. Um, the ink cloud is ... it serves to distract a predator while the octopus makes its escape.　　Um, now there's a third way that octopus can transform themselves to blend in withor mimic their environment, and that's by changing their shape and size, well, at least their apparent size.　　The muscular system of the octopus enables it to be very flexible to assume all sorts of shapes and postures. So it can contract into the shape of a little round stone, and sit perfectly still on the seafloor. Or it can nestle up in the middle of a plant and take the shape of one of the leaves. Even Proteus would be impressed, I think.
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