1 . 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.

2 . Scientists have known for years that plants respond to sounds around them. For example, flowers make sweeter nectar (花蜜) to the sound of buzzing bees. But now scientists in Israel have shown that plants also seem to be doing some “talking”.

Professor Lilach Hadany and her team at Tel Aviv University set up microphones to record tomato and tobacco plants under different conditions. Their recordings showed that the plants made ultrasonic (超声波的) sounds.

When the researchers adjusted their recordings so that humans could hear them, they heard sharp clicking noises. Plants clicked hardly at all when they had enough water. But as their soil got drier, they clicked more and more. When scientists cut off a stem (茎) from the plants, the plants also clicked more. But the clicking wasn’t the same as when the plants needed water.

It’s not clear how the plants make the sounds and whether the plants are making the sounds on purpose. But the plants are definitely making noises, and creating much more noises when they’re stressed (not enough water, stem cut off) than when they’re not.

The researchers trained an Artificial Intelligence (AI) system to identify the different kinds of clicking sounds. The system was able to tell the difference between plants that needed water and plants with cuts about 70% of the time. The result suggests that researchers may one day be able to use a plant’s sounds to figure out when it is having trouble, and what trouble it is having. That could be very helpful to farmers.

The new discovery raises many more questions. One important question is: Do plants make sounds to communicate with each other? Other research has shown that plants do seem to communicate in some ways. Plants being attacked by insects send chemicals into the air. Soon, nearby plants (that haven’t been attacked yet) start to make other chemicals that don’t taste good to insects. It’s possible that the ultrasonic sounds could work in a similar way.

1. What do the researchers find in their recordings?

A．Plants’ stems click less when they are cut off.

B．Plants click harder if they have enough water.

C．Plants make more noises when they are thirsty.

D．Flowers make sweeter nectar to the sound of bees.

2. What can we learn about the plants from paragraph 4?

A．There are still some unknown issues.

B．Not all of them are able to make sounds.

C．There are ultrasonic sounds around them.

D．They make less noises when they’re stressed.

3. What is the purpose of the AI system created by the researchers?

A．To help farmers drive away insects.

B．To identify people who are in trouble.

C．To show the growing process of plants.

D．To distinguish types of clicking sounds.

4. What might the author continue talking about?

A．Methods for plants to protect themselves.

B．Other questions raised by the new finding.

C．When plants communicate with each other.

D．Under what conditions plants attract insects.

3 . Kew Gardens is not only a popular tourist destination in London, but also a botanic garden and a research center that has the largest collection of living plants at a single site. So, let’s explore the Royal Botanic Gardens with CGTN’s reporter Robyn Dwyer.

Palm House

The first stop is the Palm House, a giant indoor rainforest with a wide range of plants. Visitors can enjoy these exotic plants while researchers can study the secrets of these flora. Eatable plants such as cocoa tree and African oil palm are all preserved here to keep the diversity of food resources. At the same time, it houses many medical use plants, including some that are used to treat cancer.

Temperate House

Known as the world’s largest Victorian glasshouse, the Temperate House is home to1,500 species of plants from temperate regions of the world. Some of the species kept here have gone extinct in the wild, such as Encephalartos woodii, a cycad from South Africa. And some are already extinct like Saint Helena olive, but the Kew has stored its DNA.

Mediterranean Garden

In the Mediterranean Garden, one can see plants from the Southern Europe, such as rosemary, olives and cork oak. Walking in the garden, one can feel the non-indoor vibe (氛围) of the Mediterranean and learn about the economic as well as scientific uses of these plants.

On International Day for Biological Diversity this year, join CGTN to travel around the world’s national parks and reserves across seven continents. Our next program is to visit penguins and seals in the Antarctic Ice Aquarium Norway. Please stay tuned!

1. What do the three stops have in common?

A．They store plants for medical use.

B．They have plants of economic value.

C．They house plants of seven continents.

D．They own plants for scientific research.

2. Which one suits a visitor preferring outdoor sites?

A．Palm House.	B．Temperate House.
C．Antarctic Ice Aquarium.	D．Mediterranean Garden.

3. Where is the text most probably taken from?

A．A botanic dictionary.	B．A TV travel series.
C．A trip advertisement.	D．A biodiversity essay.

4 . What if someone told you about a kind of grass as tall as the tallest trees? A grass as strong as steel? Would you believe that person? You should, for that grass is bamboo   (竹子), which has more than 1,000 uses. It is not just a material for making useful products. Young bamboo is eaten, often mixed with other vegetables.

Bamboo grows in many parts of the world. In the USA it grows in many states like Virginia and Florida. Most bamboo, however, is found in wet and warm climates, especially in Asia and on the islands of the South Pacific Ocean.

In most Asian countries, bamboo is nearly as important as rice. This unusual material is used to not only build large buildings but also make water pipes, musical instruments and paper. There are over 1,000 kinds of bamboo. No wonder the lives of nearly half the people on earth would change greatly if there were no longer any bamboo.

1. According to the text, bamboo is actually a kind of         .

A．grass

B．steel

C．tree

D．vegetable

2. Where does most bamboo grow?

A．Only in Asia.	B．Only in the USA.
C．In wet and warm climates.	D．All over the world.

3. What is bamboo used to do in paragraph 3?

A．Build large buildings.	B．Make water pipes.
C．Make musical instruments and paper.	D．All of the above.

4. How many kinds of bamboo are there according to the text?

A．Over 1,000.

B．Over 800.

C．Over 600.

D．Over 400.

5 . Growing at high speed and absorbing huge amounts of atmospheric carbon dioxide, could seaweeds be the key to fighting climate change? Scientists in Australia think so. In Australia, scientists are taking advantage of the power of seaweeds to absorb CO₂ at a rate that equals to the Amazon rainforest!

Kelp (巨藻) is one of the most common seaweeds. It has many types and grows at great speed. Giant kelp, for example, can grow up to 50 cm per day. Seaweeds use photosynthesis (光合作用) to absorb CO₂, and grow biomass. Seaweeds are thought to absorb nearly 200 million tonnes of our globe’s CO₂ per year.

Pia Winberg, founder of Australia’s first land-based commercial seaweed farm, suggests that growing more seaweeds could be an essential tool in the fight against climate change. “If we used the infrastructure we have in the ocean and created seaweed islands, we would actually remove many climate change issues we have today,” she said.

The Great Southern Reef is an 8,000-km network of reefs in Australia. Golden kelp forms the backbone of the network. With many other species, including giant kelp and bull kelp, growing there, it is a good place for series of relevant projects. The Great Southern Reef project managed by an independent team of seience professionals is working to promote the recognition and management of Australia’s kelp forests. The project estimates that if these kelp forests were cultivated in just 0.001% of the ocean’s surface, the amounts of the CO₂: they absorb could offset (抵消) the carbon emissions of the global aquaculture (水产养殖) industry.

Of seaweeds’ potential, there’s a long chain of wins with this.

1. What is the scientists’ attitude towards growing seaweeds to absorb CO₂?

A．Doubtful.

B．Unclear.

C．Positive.

D．Negative.

2. What can we learn about Giant kelp?

A．It can grow 50 cm per day at most.

B．It is unique to the Great Southern Reef.

C．It is cultivated in commercial seaweed farm.

D．It absorbs nearly 200 million tonnes of CO: every year.

3. Why is the Great Southern Reef suitable for ocean forest project?

A．It is managed by an independent team of science professionals.

B．It has the largest network of reefs in Australia.

C．It is home to many species of seaweeds.

D．It works to protect Australia’s kelp forests.

4. What’s the main idea of the passage?

A．Different species of seaweed absorb CO2 in different ways.

B．Bull kelp forms the backbone of the reefs network in Australia.

C．The Great Southern Reef absorbs as much CO2 as the Amazon rainforest.

D．Seaweed forests could be the key to fighting climate change.

6 . What is a “transplant?” In gardening, transplant is the process of planting seeds inside and then moving the new growth, or sprout, outside. Transplanting is easy and often costs less. You get to watch the new growth happen up close.     1     A garden expert and writer for the Associated Press, Lee Reich, can give you his advice.

To get started with transplants, you will need a container and soil.     2     Fill the containers with a special mix called potting soil and push it down — but not too much.

    3     Do this by making a small hole into the mix and put in the seeds. Cover the seeds with the potting soil and press gently again. Place the containers in a pan, or any flat, open, and larger container that could hold some water. Put water into the pan until the water reaches halfway up the containers with the seeds. After a few hours, remove them from the water.

Seeds need warmth to germinate.     4     A good average temperature for just about all seeds is about 24℃.

Now for the exciting part — waiting to see little, green sprouts! Remove all but the strongest sprout from each container.     5     Your goal now is to grow strong transplants that can survive a move to the outside garden.

In four to six weeks, most transplants should be two to three times the height of their containers. They should be strong and ready to be transplanted outside — or almost ready. Now... they are ready to go into the garden!

A．If you are new to this type of gardening, do not worry.

B．You are also an experienced gardener.

C．Then plant seeds, three or four in each container.

D．They are used to their future environment with a week of being outside.

E．The amount of warmth needed is different from plant to plant.

F．The containers should be between 5 to 10 centimeters deep.

G．Just be careful not to hurt the roots of the sprout that remains.

7 . “Best space tacos(玉米卷饼) yet,” American astronaut Megan McArthur wrote on social media Twitter on Oct 30, with a photo of her smiling from ear to ear. The taco feast celebrated the first time peppers were successfully grown on the International Space Station.

Life as an astronaut is exciting, but that doesn’t include food. Astronauts have endured packaged food for decades. “If you store packaged food for a long duration, the quality, flavor and nutritional quality decrease, the vitamins degrade,” Gioia Massa of NASA Kennedy Space Center in the US told The Guardian. Growing food in space could be crucial for astronauts on long-duration missions.

“Growing colorful vegetables in space can have long-term benefits for physical and psychological health,” said Mat Romeyn, project scientist at NASA, in a statement. The benefits of growing vegetables in space are obvious, but how are they grown?

Though astronauts have been growing plants in space for decades , cultivating edible(可食用的) food without the benefits of gravity and natural light has been difficult . A plant growth system called Veggie has been used to grow plants on the space station since 2014, according to The New York Times.

The Veggie garden is about the size of a piece of luggage and typically holds six plants. Each plant grows in a “pillow” filled with clay and fertilizer. The “pillows” are important for distributing water, nutrients and air in a healthy balance around the roots.

In the absence of gravity, plants use other environmental factors, such as light, to guide growth. LEDs above the plants produce a light suited for the plants’ growth. According to NASA, Veggie typically glows pink, which enables plants to use both blue and red wavelengths more efficiently. Other spectrums(光谱) of light, like greens, yellows or oranges, are less useful for plants.

So far, US astronauts have successfully grown 10 different crops, including lettuce and radish, on the space station since 2015, according to CNN.

1. Which word can best describe the food consumed by astronauts in space?

A．Low-nutrition

B．Tasty-flavor

C．Poor-package

D．High-calorie

2. What makes it difficult to grow plants suitable to eat in space?

A．The shortage of crop varieties

B．The objection of the International Space Station

C．The lack of gravity and natural light

D．The long-duration missions

3. What can be learned about The Veggie Garden?

A．It can hold 10 different crops for a piece of garden.

B．It has been used to grow plants on the space station for nearly six years.

C．The “pillows” can provide plants with balanced water, nutrients and air.

D．Blue, red and orange lights are important for the growth of plants.

4. What is the best title for the text?

A．Life of American Astronauts on the Space Station

B．Success of Planting in Space

C．Benefits of Growing Vegetables in Space

D．Varieties of crops on the Space Station

8 . In south Africa’s Limpopo province, a baobab tree (猴面包树) once grew so large and stood so strong that its human neighbors decided to build a pub inside the living tree’s thousand-year-old hollow trunk(树干). For 20 years, “The Big Baobab Pub” attracted tourists all over the world. But in August 2016, one of “the walls” broke. Eight months later, another huge piece broke, too. Now, five of the giant stems have collapsed and died, leaving only half of the tree standing.

Though it could sound like a result of human visitation, it's part of an alarming trend: many of the oldest, largest baobab trees in Africa have died within the last 12 years.

Stephan Woodbourne, an African scientist, said: “Of the oldest trees that we’ve looked at in Southern Africa, the three trees that are older than 2,000 years have all died in the past 10 years. Of the 11 trees that are 1,000 to 2,000 years old, six of them have died.”

A report published in the journal Nature Plants claims scores of the ancient baobab trees, some of which are up to 3,000 years old, are now dying because of rising global temperatures.

Researchers believe it is impossible that such a high number of old baobab trees die in such a short time due to natural causes. They think it may be associated with huge change of climate conditions that affect southern Africa in particular.

1. What has happened to The Big Baobab Pub?

A．The pub has largely been destroyed.

B．More tourists from the world visit it.

C．The pub has a long history of 2,000 years.

D．The Baobab Tree grows larger and stronger.

2. The paragraphs from 2 to 4 mainly tell us that ________.

A．all the oldest baobab trees have been dead

B．the oldest baobab trees will die out soon

C．ancient baobab trees are in the face of danger

D．Human’s visits lead to ancient baobab trees’ deaths

3. What is probably the main reason for the trees’ death?

A．Many pubs’ foundation.	B．Global climate changes.
C．Human visitation.	D．Natural causes.

4. What’s the best title of the passage?

A．Research on Baobab Tree.	B．Facts about Baobab Tree.
C．Baobab Tree in Africa.	D．Tree of Life is Dying.