| A．Weeds. | B．Wild flowers. | C．Flowers from store. |
2 . Between 20 and 40 per cent of planet Earth is covered in grasslands, across every continent except for Antarctica. Grass is a low-growing, flowering plant with groups of narrow leaves growing from its base. Strong roots typically hold this plant’s leaves firmly to the ground.
One of the most common sights along stretches of grass is grass-eating animals. This is because many large animals rely on extensive grasslands to survive, and grass grows well with this regular trimming (修剪). The plants gain their energy from sunlight and require healthy cells to do so. If the leaves aren’t cut, the tips die and start to rot. When they are damaged with a clean cut, however, the cells are caused to grow quicker and produce new, healthy tissue. This is also why cutting your garden’s grassland regularly can make your grass look thicker and healthier.
Humans rely on grass for food, too. Many grasses, such as w heat or corn, are harvested as a main part of some diets. Meanwhile, grass is used indirectly to produce food in the form of livestock (牲畜). Cattle farmers require grass in their fields to feed cows and sheep before they are turned into meat for human consumption.
One of the most debated questions is how long ago grass evolved. Because grass doesn’t preserve well as a fossil, a definitive answer is hard to come by. Until recently, many scientists estimated that grass began to grow on Earth between 50 and 65 million years ago.
However, within the last decade, a piece of 100-million-year-old amber (琥珀) was found that appeared to contain the oldest grass fossil to date. Studies of fossilized dinosaur faces (粪便) also suggest that some dinosaurs lived at the same time that grass grew on the planet, incorporating it into their diets.
1. What is the function of the roots mentioned in Paragraph 1?| A．To fix the leaves to the soil. | B．To store water and nutrients. |
| C．To support the growth of the plant. | D．To protect the plant from animals. |
| A．By improving soil quality. | B．By encouraging cell growth. |
| C．By preventing the tips from dying. | D．By attracting more animals to eat them. |
| A．Grass doesn’t preserve well as a fossil. | B．There are no fossils of grass available. |
| C．There is no solid evidence of its evolution. | D．Scientists can’t agree on its origin. |
| A．The Variety of Grass | B．The Development of Grass |
| C．How Grass Change Life | D．How to Make Grass Grow Well |
3 . Four Best Plants to Give as Gifts
Choosing a gift for someone is always a challenge. Giving plants is one way to try if the recipient is already a plant-lover. Here are some sure to impress as thoughtful gifts.
Jade Plant
The jade plant is a large succulent (肉质植物) that makes a perfect gift for someone who’s mastered parenting succulents. With a woody stem (茎), it looks like a tree once growing tall enough. Besides occasional watering and a bright window, the jade plant has few other requirements. A good challenge for ambitious owners is to regularly cut off its heavy leaves to reduce weight.
Christmas Cactus
This is a succulent with eye-catching flowers that appear in winter. You might assume it a picky plant, but nothing could be further than the truth. It prefers bright, indirect light and grows well in average potting soil. This plant prefers a steady watering schedule, especially in winter. To encourage more growth, plant it in a hanging container that allows its branches to hang down.
Paperwhite
Some people just aren’t interested in keeping houseplants around long-term, and paperwhite flowers are an excellent gift for anyone you know who fits this mould. Paperwhites grow from bulbs (鳞茎) and will produce flowers out of season. The roots need to be kept relatively damp, but once they are blooming (开花), there’s not much that can go wrong. They can be replanted outside after they have run their course.
Corn Plant
The corn plant is forgiving of variable light conditions and watering routines. It grows slowly, but can reach a height of four to six feet, and can make an impressive floor plant. Its leaves turn paler in direct sunlight to reflect the extra light, and darker green in shady conditions to maximize sunlight absorption.
1. Which plant requires practised gardening experience?| A．Jade plant. | B．Christmas cactus. | C．Paperwhite. | D．Corn plant. |
| A．By replanting it outside before blooming. | B．By watering it regularly during blooming. |
| C．By cutting off most of its heavy leaves. | D．By making its branches grow upwards. |
| A．The frequency of watering. | B．Its flowering time. |
| C．Its rate of growing. | D．The amount of sunlight. |
4 . For many years, scientists saw trees as independent living things. Each tree in the forest was trying to get light, water and nutrients. Trees competed for resources.
In forests, fungi connect trees through underground networks. Trees’ roots branch out in all directions. The same soil is home to fungi, which can grow on and around tree roots. The fungi grow in thin threads (线状物). As they grow, the threads can link to numerous trees. The fungi create webs between trees known as mycorrhizal (菌根) networks.
The fungi in a mycorrhizal network link the trees together.
Mycorrhizal networks are not always cooperative. Some plants will use the networks to take nutrients from their neighbors. Some flowers will steal food from other plants.
| A．Trees also send messages through the networks. |
| B．Networks can even connect different species of plants. |
| C．Scientists think the fungi are important for healthy forests. |
| D．Trees can share sugars, nutrients and water with one another. |
| E．However, scientists are discovering that trees may actually work together. |
| F．There are also plants that send poisonous substances through the networks. |
| G．In these networks, scientists think the trees and the fungi help one another. |
1. How does the woman feel at first?
| A．Curious. | B．Surprised. | C．Excited. |
| A．Flowers. | B．Mushrooms. | C．Trees. |
| A．Two. | B．Three. | C．Four. |
| A．On Thursday. | B．On Friday. | C．On Saturday. |
6 . 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. |
| 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. |
| A．They can recongnize harmful vibrations. | B．They look like laboratory mice. |
| C．They can threaten the caterpillars. | D．They can release poisonous chemicals. |
| A．Disadvantages of chemical pesticides. | B．Application of the experimental results. |
| C．Interaction between plants and insects. | D．Warning system of widespread insects. |
7 . Some of the oldest living things on our remarkable planet are trees. The record holders are bristlecone pines (狐尾松) of the western United States, quite a few of which are known to be more than 3,000 years old. One individual, discovered in 2012, is estimated to be more than 5,060 years old, making it the oldest known non-clonal tree in the world!
So, how do trees survive for thousands of years?
The other part of the answer has to do with how trees age. In fact, there is quite a debate about whether ancient trees can be considered “immortal (永生的)”. That is, will such trees ever die if they are not killed by an outside force? We may never know the answer to that, but, at the very least,
Older trees benefit greatly from having bodies made mostly of dead woody tissue. In fact, an old tree might be as much as 95 percent dead tissue! Given that it isn’t alive, wood does not require metabolic (新陈代谢的) activity to maintain it,
| A．so an old tree doesn’t really need to do much to keep living |
| B．This is a question that has something to do with the good luck of trees |
| C．However, bristlecones are certainly not alone in terms of the oldest creatures |
| D．This is a fascinating question for biologists that does not yet have a settled answer |
| E．What’s more, some ancient trees have superior chemical defenses against pests and diseases |
| F．which means that trees can survive everywhere without being limited by external and internal conditions |
| G．we know that ancient trees age in ways that are dramatically different from the ways that most animals and even other plants age |
8 . Suzanne Simard, a professor of forest ecology who called herself a “forest detective”, was raised in mountains in Canada. Few scientists make much impact with their PhD thesis, but, in 1997, she did just that. Her research on the “wood wide web” made the cover of Nature and transformed our understanding of forests. What was then a challenge to traditional ideas is today widely accepted.
A mushroom is the part of a fungus (真菌) that sticks up above the ground. Thin, white threads grow from its stem deep into the soil. These threads are called hyphae (菌丝). Hyphae connect themselves to tree roots. They also stretch from root system to root system, like an underground network. This network may go for miles. Hyphae pick up nutrients and water from soil. The fungus threads that connect to tree roots share their nutrients and water with the trees. In return, they sip a bit of the sugar the trees make. Sharing helps both trees and mushrooms live. It’s also how trees communicate.
When a tree is being eaten by bugs, it makes chemicals to shoo them away, sort of like bug repellent (驱虫剂). The chemicals travel through the tree, down its roots, and into the hyphae network. Other trees connected to the network taste the chemicals. That tells them a nearby tree is under attack, so they start to make their own bug repellent. Trees do more than share warnings through the hyphae. They also help each other. In the fall, paper birch trees drop their leaves and can no longer make sugar. So, a fir tree that stays green all winter uses the network to send extra sugar to the birch until spring comes again. This system of sharing information and nutrients through the hyphae is sometimes called the “wood wide web”, because it works a bit like the Internet.
Local climate sets the stage for the wood wide web, researchers say. In cool temperature and boreal forests, where wood and organic matter decay slowly, network-building EM fungi rule. By contrast, in the warmer tropics where wood and organic matter decay quickly, AM fungi dominate. These fungi form smaller webs and do less intertree swapping, meaning the tropical wood wide web is likely more localized.
Ecologist Thomas Crowther’s results suggest that as the planet warms, about 10% of EM-associated trees could be replaced by AM-associated trees. Microbes in forests dominated by AM fungi deal with carbon-containing organic matter faster, so they could liberate lots of heat-trapping carbon dioxide quickly, potentially accelerating a climate change process that is already happening at a frightening pace.
1. What do we know about Suzanne Simard?| A．She was a professor and a forest detective. |
| B．Growing up in the countryside, she made the cover of Nature. |
| C．Like many other scientists, she made big influence on her PhD thesis. |
| D．Her idea of the “wood wide web” used to challenge people’s thoughts. |
| A．They facilitate tree communication. | B．They form an underground network. |
| C．They produce sugar and share it with trees. | D．They share nutrients and water with the trees. |
| A．They release warning signals through leaves. |
| B．They produce real bug repellent to kill insects. |
| C．They make use of hyphae to produce chemicals. |
| D．They send chemical signals through the network. |
| A．It might slow down carbon release. | B．It would break down organic matter. |
| C．It might speed up climate change. | D．It might lead to faster tree growth. |
9 . The candy we eat, the tea we drink, the lotion we use---they all likely contain ingredients from wild plants. While natural ingredients can be beneficial to buyers, the way those plants are harvested could harm ecosystems. In a recent United Nations report, medicinal plant experts revealed the risks behind several of them, including Brazil nuts, frankincense, goldenseal, gum arabic, and licorice.
Plant derivatives （衍生物） in household products “sit there somewhere in the middle of the ingredients list” on product labels, often going unnoticed, says Caitlin Schindler, lead author of the report. Even if consumers do take note, there’s no information about what’s involved in obtaining or processing the derivatives.
Many of these plants are threatened with extinction from overharvesting, disease and pests, climate change, and habitat loss. The endangered state of more than 20,000 medicinal plant species has never been assessed, which means it’s impossible to know whether their use is sustainable.
Meanwhile, the trade in wild plants is booming. U. S. consumers spent more than $12.3 billion on herbal dietary supplements in 2021---up more than 9 percent from 2020. Wild plants have been used locally for centuries, but today’s global demand puts many at risk. And international customers often have no idea where these products originate.
Should consumers stop buying the products? No. Schindler says, because “the ingredients are really critical to a lot of people’s livelihoods.” Solutions for transforming the trade in wild plants are rooted in awareness. The first step for consumers is to “just notice that you’re buying something that has a wild ingredient,” she says. It’s generally safer to purchase local products and splurge on more expensive ones, if possible.
Consumers can also look for organic and fair-trade certifications. Various programs evaluate wild-plant supply chains for sustainability, and many companies advertise these certifications, either on the product or online. One of the most prominent is Fair Wild, which assesses environmental risks and recommends best sourcing practices. If certifications are missing, Schindler encourages people to challenge companies to do better. “Until businesses get a bit more pressure from consumers, we won’t see any changes happening,” she says.
1. What can we learn about wild plants according to the report?| A．Their current situation is ignored. | B．They are limited on a global scale. |
| C．They have been evaluated regularly. | D．Their process information is on the label. |
| A．Get rid of. | B．Spend much money on. |
| C．Pay attention to. | D．Conduct many experiments on. |
| A．They confirm the quality of the wild plants. |
| B．They offer consumers rights to assess the products. |
| C．They ensure the use of wild plants at a steady level. |
| D．They inspire companies to make more advertisements. |
A． | B． | C． | D． |
10 . In 1986, when he was only a prince. King Charles told a television interviewer that it was important to talk to plants. He was widely laughed at. But his wisdom seems to have been ahead of its time, for there is now plenty of evidence that plants can detect (察觉) sound, react to it, and even perhaps produce it.
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, announced that an Asian plant grew much larger leaves when exposed to 56 days of Buddhist chants — but not if it was exposed to Western pop music, or silence. Another, published last year, found that plants exposed to the noise of traffic from a busy motorway suffered slow growth, and produced a range of stress compounds (成分).
Another research reports that certain frequencies (频率), played in some environments like greenhouses, can affect seed growth and even improve crop production. And plants can make noises, too. Earlier this year a group of researchers at Tel Aviv University published an article in Cell Press, reporting that several plants gave out different noises in response to different stresses — although not at the sorts of frequencies that humans can hear. Humans can only hear frequencies of up to 16 kilohertz. Scientists discovered sounds given out by plants were up to 250 kilohertz.
If all that sounds strange, perhaps it should not. After all, sound carries useful information.
From an evolutionary point of view, there is no reason to expect that information to be applied only by animals.
1. What was most people’s attitude to Charles’ opinion?| A．Unclear. | B．Positive. | C．Cautious. | D．Negative. |
| A．Different sounds have different effects on plants. |
| B．Buddhist chants don’t make a difference to plants. |
| C．Western pop music does good to plants’ growth. |
| D．The noise of traffic produces stress compounds. |
| A．The sounds are strange. | B．The plants grow in greenhouses. |
| C．The plants are under great stress. | D．The sounds are at high frequencies. |
| A．It’s the important to talk to plants. |
| B．Sounds make a difference to plants. |
| C．Plants can discover and even make sound. |
| D．Humans can’t hear sounds produced by plants. |
