【推荐1】Dr Paul King at Texas Christian University has been an influential scholar in the field of communication studies for 30 years. I spoke to King about his research into “state anxiety in listening performance”. Most of us believe that anxiety impacts only the person giving the speech or presentation. Dr King has discovered that audience members feel anxiety, too.

King says that listening is a tiring activity because the learner is continually adding material to be remembered-retrieved-later. This is what he means by “cognitive backlog(认知积压)”. Put simply, the longer the task or the more information that is delivered, the greater the cognitive load. According to King, listening to a five-minute presentation produces a relatively small amount of cognitive backlog; an 18-minute presentation produces a little more, while a 60-minute presentation produces so much backlog that you risk seriously upsetting your audience unless you create a very engaging presentation with “soft breaks”— stories, videos, demonstrations, or other speakers.

The longer the presentation, the more the listener has to organize, comprehend, and remember. The burden increases along with a listener’s anxiety. They become increasingly frustrated, even angry. King says that the current research into memory processing suggests that it’s better to study content on two or three occasions for a short period of time instead of spending an entire evening cramming(填鸭式学习).

King applies the results to his graduate class on research methods. If given a choice, most graduate students would rather attend a single three-hour class than three 50-minute classes. When King taught his class once a week, he found that the students returned for the next class having lost most of the information they had learned the prior week. King discovered the “better practice” was to schedule the same content on three separate occasions, such as Monday, Wednesday, and Friday. King said that despite objections, when he taught the class on three occasions his students scored better and exhibited a better memory of the complex material.

1. What does Dr Paul King say about “cognitive backlog”?

A．It should be prevented from happening.

B．It is affected by the number of listeners.

C．It changes with the length of a presentation.

D．It produces a negative effect on mental health.

2. What is the function of “soft breaks”?

A．To ease listeners’ anxiety.	B．To show the talents of speakers.
C．To add topics to the presentation.	D．To make the presentation longer.

3. What does Dr Paul King’s new practice focus on?

A．Exploring complex materials.	B．Completing a single task at a time.
C．Breaking up the whole into parts.	D．Grouping students by their levels.

4. What can we learn about Dr Paul King’s new class schedule?

A．It was welcomed by students.	B．It turned out to be a success.
C．It made no difference indeed.	D．It still had room for improvement.

【推荐3】Brown rice is a tough sale when offered next to white. Despite the fact that brown rice is healthier, people prefer white rice because they think it just tastes better, just like folks opt for white bread instead of whole wheat. White rice and brown rice begin as the same thing—they come from the same grain, after all. But white rice is different from brown rice in terms of processing.

When rice is first harvested, it is washed, and the outer covering is removed from the grains. At this point, what you’re left with is brown rice. It still has several thin layers of bran coating the grain. To get white rice from that grain, it also has to be milled and polished down, removing the bran. That is why brown rice is a whole grain. It contains all parts of the grain, including the fibrous bran, the nutritious germ and endosperm. White rice has had the bran, the germ, much of the fiber, vitamins and other nutrients removed.

One cup of cooked brown rice contains 4 g of fiber and 5 g of protein, while one cup of cooked white rice contains only 1 g of fiber and 4 g of protein. But fiber isn’t the only benefit of brown rice. Studies have found that it can reduce the risk of diabetes.

One of the reasons white rice has soared in popularity is that it’s easier to cook. Not only does it take less time because the fibrous bran has been removed, but it turns out with a soft, delicious result more often than not. What makes brown rice so hard to prepare is the fact that you have to cook it long enough to soften the bran, but not so long that the inner grain turns mushy. This is tricky, but it’s not impossible. There are many foolproof methods you can use. One is to get a rice cooker, but if you’re not up for another appliance on your kitchen counter, there are other options.

1. How does the author lead in the topic of the text?

A．By making a comparison.	B．By quoting a proverb.
C．By using imagination.	D．By listing data.

2. Which of the following is a difference between white rice and brown rice?

A．White rice is thicker.	B．Brown rice has better taste.
C．Brown rice is less processed.	D．White rice contains more vitamins.

3. What makes white rice easier to cook compared to brown rice?

A．Having no bran.	B．Containing more fiber.
C．Having no endosperm.	D．Containing more protein.

4. What is the author’s attitude to eating brown rice?

A．Doubtful.

B．Supportive.

C．Tolerant.

D．Curious.

【推荐1】A new study reveals that trees can communicate and warn each other of danger. “For the first time, researchers have been able to visualize plant-to-plant communication,” said Masatsugu, senior author of the study.

The idea of talking trees started to take root in the 1980s. Two scientists found that damaged trees began producing chemicals that made their leaves unappetizing and indigestible to discourage insects. The trees then sent chemical signals to one another through the air. Over the past four decades, scientists have observed this cell-to-cell communication in more than 30 plant species.

Past research shows plants communicate with their surroundings by releasing chemicals known as volatile (易挥发的) organic compounds. One class of these compounds are released when a plant is injured: green leafy volatiles. These are released by, as the name suggests, pretty much every green plant with leaves, and are produced when a plant experiences physical damage. An example of these compounds is the smell released from fresh-cut grass.

In the new study, Masatsugu and his colleagues manually damaged leaves and placed insects on tomato plants to trigger the release of various green leafy volatiles. After testing many of them, the team found it seemed to increase calcium ions (钙离子) inside cells. The calcium signaling is like a switch to turn on the defense responses from the plants.

With this new understanding, researchers say plants could be immunized against threats and stressors before they even happen. For instance, exposing healthy plants to insect-ridden plants or the associated green leafy volatiles could boost their genetic defenses, so farmers use less pesticides. The revelation could also help make plants more resilient (有复原力的) during a drought, signaling the plants to conserve more water.

1. What does the new research find?

A．Trees can inform other trees of potential threats.	B．Trees can make themselves attractive.
C．Trees will send signals first once damaged.	D．Trees will work together to trick insects.

2. What can be learnt about green leafy volatiles?

A．They defend insects.	B．They kill insects.
C．Some of them can be smelt.	D．Some of them can be seen.

3. How was the study carried out by Masatsugu?

A．By protecting trees from insects.	B．By classifying green leafy volatiles.
C．By increasing calcium ions inside cells.	D．By causing the release of certain chemicals.

4. What aspect of the new study does the last paragraph focus on?

A．Its target.

B．Its process.

C．Its application.

D．Its background.

【推荐2】When I was a kid, a sycamore (枫树) grew in front of my home. At the age of 10, I was just tall enough to reach its lowest branch and lift myself into its embrace. Sometimes two or three of my friends would join me in the sycamore, or in the maple down the street, or Mrs. DiMarco’s old peach tree, some of whose stout horizontal branches allowed us to sit shoulder to shoulder, eating sweet fruit.

In my small town there are some kinds of trees, their branches spreading wide, open for business. But I have not yet seen a climber. Perhaps computer games have replaced tree climbing, or maybe the activity went the way of monkey bars, which came to be viewed as too risky and have largely disappeared from playgrounds.

It is a sad loss. I have always believed that, since low-hanging branches provide no benefit to the tree, they must be meant for the child. Robert Frost understood this when he wrote:

When I see baches (桦树) bend to left and right,

Across the lines of straighter darker trees,

I like to think some boy’s been swinging them.

My only disagreement with Frost is his inference that tree climbing is a gender-specific task. Both boys and girls make a joyful climb.

The campus of the university where I teach has all sorts of trees. During a recent walk, I found myself bending under the branch of an immense spruce (云杉). I grabbed the thing, and a moment later was sitting on a branch. Then the memories came flooding back. The old sycamore, the friends, and finally, the reluctance to return to earth when the parental call to supper came.

I was so lost in my thoughts that I didn’t hear the student calling to me from below. He asked what I was doing. I didn’t waste time on explanations. “Come on up,” I said “The air’s fine.” But he only laughed and waved me off. He didn’t know what he was missing.

1. What does the underlined word “stout” in Paragraph 1 probably mean?

A．Slim.

B．Bent.

C．Smooth.

D．Strong.

2. What is the second paragraph mainly about?

A．Why kids don’t climb trees.

B．Why monkey bars are dangerous.

C．Why there is no business under trees.

D．Why kids are addicted to computer games.

3. What does the author want to prove by mentioning Robert’s poem?

A．Some branches of trees are useless.

B．Trees are intended for kids to climb.

C．Trees are a source of inspiration for poets.

D．Climbing trees is a unique right of boys.

4. What did the author think the student had missed?

A．The explanations to his question.

B．The fresh air above the tree.

C．The pleasure of climbing trees.

D．The sense of safety on earth.

【推荐3】Scientists have been experimenting with playing sounds to plants since at least the 1960s, during which time they have been exposed to everything from Beethoven to Michael Jackson. Over the years, evidence that this sort of thing can have an effect has been growing. One paper, published in 2018, claimed that an Asian shrub known as the telegraph plant grew substantially larger leaves when exposed to 56 days of Buddhist music — but not if it was exposed to Western pop music or silence. Another, published last year, found that marigolds and sage plants exposed to the noise of traffic from a busy motorway suffered growth difficulty.

Plants have been evolving (进化) alongside the insects that eat them for hundreds of millions of years. With that in mind, Heidi Appel, a botanist now at the University of Houston, and Reginald Cocroft, a biologist at the University of Missouri, wondered if plants might be sensitive to the sounds made by the animals with which they most often interact. They recorded the vibrations made by certain species of caterpillars (毛毛虫) as they chewed on leaves. These vibrations are not powerful enough to produce sound waves in the air. But they are able to travel across leaves and branches, and even to neighbouring plants if their leaves touch.

They then exposed tobacco plant — the plant biologist’s version of the laboratory mouse — to the recorded vibrations while no caterpillars were actually present. Later, they put real caterpillars on the plants to see if exposure had led them to prepare for an insect attack. The results were striking. Leaves that had been exposed had significantly higher levels of defensive chemicals, making them much harder for the caterpillars to eat. Leaves that had not been exposed to vibrations showed no such response. Other sorts of vibration — caused by the wind, for instance, or other insects that do not eat leaves — had no effect.

“Now speakers with the right audio files are more often being used to warn crops to act when insects are detected but not yet widespread,” says Dr. Cocroft. “Unlike chemical pesticides, sound waves leave no dangerous chemicals.”

1. What can we learn about plants from the first paragraph?

A．They may enjoy Western music.	B．They can’t stand Buddhist music.
C．They can react to different sounds.	D．They can make different sounds.

2. What’s the basis for Appel and Cocroft’s research?

A．Plants can make a cry for help.	B．Plants evolve alongside insects.
C．Plants are sensitive to the sounds.	D．Plants have been studied for years.

3. What can we infer about plants from Paragraph 3?

A．They can recongnize harmful vibrations.	B．They look like laboratory mice.
C．They can threaten the caterpillars.	D．They can release poisonous chemicals.

4. What does the last paragraph mainly talk about?

A．Disadvantages of chemical pesticides.	B．Application of the experimental results.
C．Interaction between plants and insects.	D．Warning system of widespread insects.