1 . The world loves a cup of tea. It only takes a few grams to make a cup of tea and millions of tons of tea are consumed every year. Tea can be good for you because it contains some things that help lower cholesterol and reduce the risk of cardiovascular disease. Tea also contains caffeine(咖啡因), which improves not only mental alertness but can also increase anxiety and cause other problems.

What would be agreeable is a tea plant that provides all the taste and goodness but with little or none of caffeine. Chen Liang and Jin Jiqiang in the Tea Research Institute, Chinese Academy of Agricultural Sciences think they have found just such a plant, growing wild in a remote area in southern China’s Fujian Province. Known locally as hongyacha, the discovered plant grows only between 700 meters and 1,000 meters above sea level around a handful of Chinese villages. As they report in the Journal of Agricultural and Food Chemistry, not only is the tea plant naturally caffeine-free but it also contains a number of unique medicinal compounds that, the locals believe, offer considerable health benefits.

The researchers are now exploring methods to protect hongyacha in its natural habitat while further studies are carried out. It can take time—and sometimes it does not work—for new plant varieties to be bred for commercial use. A pair of naturally caffeine-free coffee plants were discovered in 2003, but little progress has been reported. Tea lovers will be watching hongyacha with interest. And others will wonder what else is out there.

1. What’s the disadvantage of drinking tea according to paragraph 1?

A．It can make people hard to sleep.	B．It can make people feel anxious.
C．It can get people addicted.	D．It can take people much time.

2. What can we learn about hongyacha in paragraph 2?

A．It is nothing but just medicine.	B．It can only survive in greenhouses.
C．It is a good pick for caffeine lovers.	D．It has a good taste and little caffeine.

3. What might the follow-up study focus on about hongyacha?

A．Its future location.	B．Its natural habitats.
C．Its future market.	D．Its production process.

4. Where is the text probably taken from?

A．A health magazine.	B．An advertising brochure.
C．A travel guidebook.	D．A newspaper.

2 . High-resolution (高分辨率) satellite imagery has been used to map every single tree in Africa, showing a technique that could help improve the monitoring of deforestation (森林砍伐) across the world. Florian Reiner at the University of Copenhagen, Denmark, and his colleagues used images from sate lies to map canopy (树冠) across the entire African continent.

Modern sate lies usually catch tree canopies at a resolution of 30 meters — fine for measuring the size of forests, but less good at mapping individual trees. The satellite data Reiner and his colleagues used had a resolution of 3 meters, enabling the study to map all trees, including those not part of a forest.

The results suggest that 30 percent of all trees in Africa aren’t in a forest and instead are across farmland, savannah and urban areas. “Many countries in Africa lack thick forests, but have a lot of trees.” says Reiner. “These trees are extremely important to the local ecosystems, the people and the economy. By tracking every single tree, researchers can start to monitor how these trees are coping with climate change or whether they are sensitive to deforestation.” It could also improve the monitoring of reforestation efforts, which are growing in popularity as a way of removing carbon dioxide from the atmosphere.

“At a local level, being able to consistently monitor when and where trees are disappearing or reappearing can lead to more actionable insights,” says John Francis at the Alan Turing Institute in London.

“The study is a proof of concept rather than a map ready for immediate commercial use,” says Reiner. “It’s research work. It’s showing what could be done,” he says. But he is already working with colleagues to scale up the tracking approach to cover the entire global canopy: “We’re hoping that this will be seen as a way forward in monitoring tree resources.”

1. Why is high-resolution satellite imagery used to map every single tree?

A．To know the exact height of the tree.

B．To have a clear picture of the canopy.

C．To help monitor the deforestation.

D．To improve the satellite technology.

2. What is John Francis’ attitude towards the map?

A．Doubtful.

B．Disapproving.

C．Indifferent.

D．Favorable.

3. What do Reiner and his colleagues expect to do?

A．Protect the trees only in Africa.

B．Put the map into commercial use.

C．Track the entire global canopy.

D．Improve the imagery technology.

4. What is probably the best title?

A．Ways to Measure the Size of Forests in Africa

B．Coping with Climate Change by Tracking Every Single Tree

C．A Map from the Satellite Ready for Immediate Commercial Use

D．High-resolution Satellite Imagery Used in Monitoring Deforestation

3 . It has long been known that plants communicate when they are stressed. You need only observe a houseplant to realize that a plant wilts (枯萎) when it needs water. Some plants may also emit a terrible taste to prevent some insects from hurting them.

Now, a new study that was conducted by researchers at Tel Aviv University, shows that not only do plants express themselves in the above ways when stressed, they also make sounds, like talking.

According to the researchers, plants make sounds at frequencies (频率) between 40 to 80 KHZ — out of the range of human ears — but within the range of some animals. “Bats make sounds in these ranges all the time, and mice, dogs and cats can partially hear within it,” Dr. Lilach Hadany, a Professor at Tel Aviv University, and one of the authors of the study said.

One of the primary breakthroughs (突破) of Hadany’s study is that the researchers have managed to understand and classify the sounds that plants make for the first time. Plants that are not stressed make about one noise per hour, but plants that are stressed or injured make many hundreds of sounds per hour. And each of these sounds seemed to be specific to the type of stress the plant was under.

This type of information could be important for agriculture. Knowing what sounds their plants are making could help farmers determine whether their crops are in danger of drought or disease and allow them to make the necessary changes to help their plants.

Amazingly enough, the researchers are not actually sure how the plants make sounds. But anyway, the discovery is still a game-changer for plant science, and potentially for the future of agriculture. One day soon your plants may be able to tell you if they are hungry, thirsty, or just feeling lonely.

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

A．Give off.	B．Add to.
C．Clear up.	D．Take in.

2. Which of the following is most likely to hear plants talk?

A．Humans.	B．Bats.
C．Mice.	D．Dogs.

3. What is the breakthrough of Hadany’s study?

A．They’ve found plants can communicate with each other.

B．They’ve used plants’ sounds to improve agriculture.

C．They can understand and classify plants’ sounds.

D．They’ve discovered how plants make sounds.

4. What can be a best title for the text?

A．Scientists Discover the Language of Plants

B．Animals Understand Plants’ Language

C．Plants Communicate in Various Ways

D．Stress Makes Plants Talk

4 . One New Year’s Day, ecologist Rob Wolton came up with an unusual resolution—to spend the next 12 months studying a hedge(树篱) 40 metres from his house in the middle of Devon. He wanted to make a list of every plant, animal and fungus(真菌)that used it. After a year of observations he had found 2, 000 species—far more than he imagined. Wolton says he enjoyed it hugely and his findings contribute to the growing body of evidence that hedges should not be overlooked.

“There is increasing recognition that much of the wildlife finds shelter in the hedges. But they’re much more than just wildlife passages—they are really important as habitats in their own right,” he says. The European commission’s Joint Research Centre recently argued that as the climate crisis worsens, hedges are expected to play more roles as they move in response to environmental change. Their deep roots help sequester carbon(固碳), and they also reduce the likelihood of flooding downstream, suck nutrients and pollutants out of water, and prevent soil loss. Alongside these functions, there is a cultural benefit to hedges too—I think lots of us who live in England think of the hedge landscape as being quite typical, says Wolton.

After the Second World War many hedges were removed to create more productive land. Only about one in three hedges in England are in good condition, according to the most recent research done in 2017.

The main issues are hedges being cut too severely and too frequently, which leads to loss of wildlife and gaps. A squirrel, for example, will turnaround if there is a gap of five metres. New hedges are being planted with single species, instead of many, which decrease the wildlife they can support.

It’s hard to say if interest in hedges will translate into action on a national scale，and much depends on what landscape features Environmental Land Management scheme.

1. What is the significance of Wolton’s study of the hedge?

A．It makes Wolton’s resolution come true.

B．It shows Wolton’s fondness of the hedge.

C．It indicates the important role of the hedge.

D．It points out the number of animals and plants.

2. What does Paragraph 2 mainly talk about?

A．Hedges provide home for wildlife.

B．Hedges are used to fight climate crisis.

C．Hedges area typical symbol of England.

D．Hedges have advantages in different aspects.

3. Why does the author mention “A squirrel” in Paragraph 4?

A．To show the diversity of wildlife in hedges.

B．To explain the bad effect of gaps in hedges.

C．To call for more species of plants in hedges.

D．To present what the loss of wildlife is like.

4. What can we infer from the last paragraph?

A．The favorable policy on hedges is undecided.

B．Public attention in hedges will be intensified.

C．A national scale protection is soon underway.

D．Environmental Land Management will fund hedges.

5 . “A beautiful field of flowers can be a rather noisy place. It’s just that we can’t hear the sounds.” Scientists at Tel Aviv University have conducted a six-year experiment, proving that plants make noise in certain stressful situations.

Plants produce a high frequency (频率) clicking sound, and when short of water, or damaged, the clicks become far more regular. They also made different sounds, depending on whether they were thirsty or injured. “Each plant and each type of stress is related to a specific sound,” said Professor Lilach Hadany, who led the research study.

Focusing particularly on tomatoes, wheat and corn, the plants were placed in a soundproof(隔音的)room and recorded by microphones. Some plants were starved of water, others cut, and a control group was left undamaged. The researchers used an algorithm (算法) to separate the noises, suecessfully telling the difference between the sounds depending on whether they were dry or cut. The algorithm did this in a greenhouse setting which included far more surrounding sounds, but it was still able to recognize the particular cries for help of the plants.

On average, the human ear can hear sounds up to around 20kHz, while the sounds produced by plants are in the 40-80kHz region, far beyond our hearing. “The sounds made by plants can’t be heard by humans but can probably be heard by various animals, such as bats, mice and insects,” Hadany tells us. Though this has yet to be proven, it’s possible that these creatures use this information to choose which plants to eat.

A study led by Reda Hassanien of China Agriculural University in Beijing years ago, also proved that plants reacted to sound waves, with some plants greatly increasing their yield. While evidence shows that plants can react to sounds, there’s no evidence today that they can actually hear them.

1. What can we know from the six-year experiment?

A．Plants of different types make the sound of the same frequeney.

B．Plants produce more regular sound in certain stressful situations.

C．Plants make sounds with a much lower frequency when stressed.

D．Plants make the sound of the same frequeney whatever the situation.

2. What is the algorithm used for in the research?

A．To record the sounds.	B．To control the sounds.
C．To produce the sounds.	D．To identify the sounds.

3. What has been proven by scientists according to the passage?

A．Plants can hear each other’s cry for help.

B．Animals can hear the sounds made by plants.

C．Plants can make sounds and respond to sound waves.

D．Animals decide what to eat based on the sounds plants make.

4. Which of the following is the best title of the text?

A．Sounds That We Can’t Hear

B．Beautiful Songs from Plants

C．Plants React to Different Types of Stress

D．Plants Talk, Especially When Stressed

6 . During the holidays, many people hang mistletoe (槲寄生) over doorways. People share kisses under this evergreen plant. It is a popular Christmas tradition. But don’t let the image of romantic plant used during the happy times of the holidays fool you. In the forests they’re from, mistletoe plants can do some real damage. Let’s take a look at how and why.

The mistletoe plant is evergreen. This means it has leaves that remain green throughout the year. It is also poisonous and has white berries (浆果) and small, yellow flowers. The mistletoe lives on other plants, taking water and nutrients from them. For this reason, mistletoe plants are considered parasites (寄生植物).

The white berries of mistletoe plants contain seeds. Some birds and mammals like to feed on these berries. When they do, the seeds may stick to the animal eating the berries. The animal may carry the seeds to another part of the tree of bush. They may also carry the seeds to another plant altogether. The seeds start to grow roots that dig through the bark of the tree or bush. The roots grow into the tissues of the plant they’ve taken over. That’s how mistletoe plants take nutrients and water away from the host plants. Mistletoe can be hard to remove once it infects (感染) a plant. The best way to fight off a mistletoe infection is to cut off the infected branch completely. If the mistletoe takes over more parts of the plant, it can start to weaken the plant and make it harder for it to grow.

As mistletoe plants grow in the trees, they become a thick mix of branches and roots. This big mass is sometimes called a “witch’s broom.” Some animals nest in these witches’ brooms.

1. What is the effect of the mistletoe on host plants?

A．It makes the plants turn green.

B．It makes the plants attacked by pests more frequently.

C．It affects the growth of the plants.

D．It stops the plants producing nutrients and water.

2. What do we know about the mistletoe from the passage?

A．It provides water and nutrients for other plants.

B．It is a poisonous evergreen plant.

C．It stands for peace during the Christmas holidays.

D．It has some magic power like a witch’s broom.

3. What is the best title for the text?

A．An Unlikely Parasite: Mistletoe	B．A Widespread Plant: Mistletoe
C．A Witch’s Broom: Mistletoe	D．A Popular Gift: Mistletoe

7 . There are many theories that suggest different ways of improving memory or thinking more clearly. One of those is the idea that adding rosemary (迷迭香) to your food or water, or even breathing in its fragrance, can give your brain a boost.

First, it’s important to understand what rosemary is.     1     It’s a perennial, meaning that once you plant it, it should re-grow every year when the weather is warm enough for it to do so. It’s native to Asia and the Mediterranean.     2    

Rosemary is related to the mint (薄荷) family of plants. When it blooms, its flowers are white, purple, pink or deep blue. It is often used as a flavor in food, including soups, meat, fish and other Mediterranean food. And it has a somewhat bitter flavor. Some people also enjoy tea flavored with rosemary.     3    

One study that involved 28 older adults found that consumption of a small amount of dried rosemary powder was associated with statistically significantly improved memory speed.     4     Researchers found that their memory of images and numbers improved when the essential oil of rosemary was sprayed in the room.

    5     But one theory is that rosemary appears to have some antioxidant (抗氧剂) properties that may offer some healing for the damage in our bodies. Another idea is that rosemary appears to lower anxiety, which in turn, may increase the ability to concentrate.

While rosemary shows some promise for boosting our brain power, it’s important to check with your doctor before you begin having it.

A．But it is grown in the United States, as well.

B．Rosemary is a herb with needle-like leaves.

C．Here’s what research has found about rosemary.

D．It is unknown if those benefits would hold true for humans.

E．It’s not known for sure why there may be a benefit from rosemary.

F．Rosemary is also used as a perfume and added to shampoo and soap.

G．Another study was performed with 53 students between 13 and 15 years old.

8 . Can plants talk? Modern research has found something amazing: they do communicate with each other.

It has been known for some time that plants use chemicals to communicate with each other. This happens when a plant gets attacked by insects. The plant gives out chemicals from the leaves that are being eaten. This is like a warning, or a call for help： "I'm being attacked! " When another plant gets the chemicals, it starts to give out its own, different chemicals. Some of these chemicals drive insects away. Others attract the wasps（黄蜂；蜜蜂）！ The wasps kill the insects that are eating the plants. Scientists hope to learn more about this plant warning system, so that we can use it to grow more crops.

More surprisingly, plants also use sound to communicate. People can't hear these sounds ； but plants are making them. Some plants make noises with their roots. Corn and chili plants do this. Some trees make clicking noises when there is not enough water.

Most surprisingly of all, plants have an amazing system of communication that can link nearly every plant in a forest. Scientists call this system the “ wood wide web”. The wood wide web is linked underground by fungi（霉菌）.It links the roots of different plants to each other. It is in some ways similar to the Internet we use. Using the wood wide web, plants can share information and even food with each other. However, it may lead to bad effects. Plants may use it to steal food from each other,     or spread chemicals to attack other plants. Perhaps one day scientists will learn how to create a “firewall“ to help prevent these attacks within the wood wide web.

Scientists are learning more every day about the secret ways in which plants talk to each other. Maybe one day we will know enough about plant communication to be able to "talk” with them ourselves.

1. What will plants do when they are attacked by insects?

A．They will kill the insects by themselves.

B．They will control the wasps to kill the insects.

C．They will send out signals to ask for help.

D．They will produce chemicals as a warning or a call for help.

2. How is the wood wide web linked by fungi?

A．By making noises with their roots.

B．By connecting the roots of different plants to each other.

C．By sharing food and information with each other.

D．By spreading chemicals to each other.

3. What is the structure of the passage?

A．	B．
C．	D．

4. Which is the best title for the passage?

A．The Secret Language of Plants

B．The Study About the Plant Warning System

C．The Plants that Give Warnings

D．Why Scientists Do Research About Plants