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        2020年12月大學(xué)英語(yǔ)四級(jí)備考閱讀精選三篇

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        沒(méi)有被折磨的覺(jué)悟,就沒(méi)有向前沖的資格。既然選擇了,就算要跪著也要走下去。其實(shí)有時(shí)候我們還沒(méi)做就被我們自己嚇退了,想要往前走,就不要考慮太多,去做就行了。以下為“2020年12月大學(xué)英語(yǔ)四級(jí)備考閱讀精選三篇”,歡迎閱讀參考!更多相關(guān)訊息請(qǐng)關(guān)注!
            
            【篇一】2020年12月大學(xué)英語(yǔ)四級(jí)備考閱讀精選
            people appear to born to compute. The numerical skills of children develop so early and so inexorably(堅(jiān)定地) that it is easy to imagine an internal clock of mathematical maturity guiding their growth. Not long after learning to walk and talk, they can set the table with impress accuracy---one knife, one spoon, one fork, for each of the five chairs. Soon they are capable of nothing that they have placed five knives, spoons and forks on the table and, a bit later, that this amounts to fifteen pieces of silverware. Having thusmastered addition, they move on to subtraction. It seems almost reasonable to expect that if a child were secluded on a desert island at birth and retrieved seven years later, he or she could enter a second entera second-grade mathematics class without any serious problems of intellectual adjustment.
            Of course, the truth is not so simple. This century, the work of cognitive psychologists has illuminated the subtle forms of daily learning on which intellectual progress depends. Children were observed as they slowly grasped----or, as the case might be, bumped into---- concepts that adults take for quantity is unchanged as water pours from a short glass into a tall thin one. Psychologists have since demonstrated that young children, asked to count the pencils in a pile, readily report the number of blue or red pencils, but must be coaxed(說(shuō)服) into finding the total. Such studies have suggested that the rudiments(基本原理) of mathematics are mastered gradually, and with effort. They have also suggested that the very concept of abstract numbers-----the idea of a oneness, a twoness, a twoness that applies to any class of objects and is aprerequisite(先決條件) for doing anything more mathematically demanding than setting a table----is itself far from innate.
            【篇二】2020年12月大學(xué)英語(yǔ)四級(jí)備考閱讀精選
            Taste is such a subjective matter that we don't usually conduct preference tests for food. The most you can say about anyone's preference, is that it's one person's opinion. But because the two big cola(可樂(lè)) companies Coca-Cola and Pepsi Cola are marketed aggressively, we've wondered how big a role taste preference actually plays in brand loyalty. We set up a taste test that challenged people who identified themselves as either C0ca-Cola or Pepsi fans: Find your brand in a blind tasting.
            We invited staff volunteers who had a strong liking for either Coca-Cola Classic (傳統(tǒng)型)or Pepsi, Diet (低糖的)Coke, or Diet Pepsi-These were people who thought they'd have no trouble telling their brand from the other brand. We eventually located 19 regular cola drinkers and 27 diet cola drinkers.
            We eventually located 19regular cola drinkers and 27diet cola drinkers. Then we fed them four unidentifiedsamples of cola one at a time, regular colas for the one group, diet versions for the other. We asked themto tell us whether each sample was Coke or Pepsi; then we analyzed the records statistically to compare the participants 'choices with what mere gum-work would have accomplished.
            Getting all four samples right was a tough test, but not too tough, we thought, for people who believed they could recognize their brand. In the end, only 7out of19regular cola drinkers correctly identified theirbrand of choice in all four trials. The diet-cola drinkers did a little worse -only 7of27identified all four samples correctly.
            While both groups did better than chance would predict, nearly half the participants in each group made the wrong choice two or more times. Two people got all four samples wrong. Overall, half the participants did about as well on the last round of tasting as on the first, so fatigue, or taste burn out, was not a factor. Our preference test results suggest that only a few Pepsi participants and Coke fans may really be able to tell their favorite brand by taste and price.
            【篇三】2020年12月大學(xué)英語(yǔ)四級(jí)備考閱讀精選
            Henry III didn't know much about biology. He went through six wives back in the 1500s, looking for one whocould bear him a son. Scientists now know that it's the father's sperm, not the mother's egg, which determines whether a baby is a boy or a girl. And last week researchers at the Genetics and IVF Institute, a private fertility(生育能力)center in Virginia, announced a new technique that will allow parents to choose the sex of their baby-to-be, before it has even been conceived. The scientist used a tiny laser detector to measure the DNA in millions of sperm cells as they pass single file through a narrow tube, like cattle being herded through a corral(牲口欄). In a study published last week, "girl sperm," which has more DNA—the genetic material— in each cell, was collected, while "boy sperm" was discarded. And when purified girl sperm was used to impregnate(使受孕)a group of mothers, 15 of 17 resulting babies turned out to be girls.
            The researchers say that "sex selection" can also double a mother's chance of having a son and can be usedto avoid genetic diseases that affect only one gender, such as hemophilia(血友病). But some experts, like New York University fertility specialist Dr. Jamie Grifo, worry that sex selection could lead to a kind ofin uteri(子宮)discrimination, especially in cultures where sons are considered superior to daughters. "It's valuing one gender' over another," Grifo says. "I don't think that's something we should be doing." So far, patients at the institute have been asking for both boys and girls, in order to "balance" their families. And some ethics experts say that's fine, as long as parents are just looking for a little gender variety. "If you have three boys, and you want a girl," says University of Texas reproductive-law professor John Robertson, "that's not gender bias at all."