1 . When scientists talk about recent extinctions, birds and mammals (哺乳动物) get most of the attention. But the first global analysis of its kind finds it is twice as many plants that have disappeared as birds, mammals, and amphibians (两栖动物) combined.

Researchers reviewed published research, international databases, and museum specimens such as grasses from Madagascar, finding that 571 plants species have gone extinct in the past 250 years. One reason why the total is higher than that of the well-studied animals is that there are simply more species of plants. Looking at percentages, the situation is worse for mammals and birds. An estimated 5% of those species have gone extinct, compared with 0.2% of plants.

The loss includes the Chile sandalwood tree in the South Pacific, which was cut down for its fragrant (芳香的) wood. It was last seen on Robinson Crusoe Island in 1908. The extinction rates among plants have been highest for trees and shrubs on islands, which often have species that occur nowhere else, and in regions with rich diversity, especially the tropics and in Mediterranean climates.

Just a few years later, the world lost the banded Trinity (Thismia americana), a leafless plant that grew entirely underground except for its flowers. Most species of this kind of plant grow in rainforests, but this plant was first described in 1912 in a sandy wetland in Chicago, Illinois, and was wiped out by development.

According to the team’s report in Nature Ecology & Evolution, the total of 571 extinct plant species is four times higher than the official listing kept by the International Union for Conservation of Nature. Even so, it is probably still an underestimate (低估), as less is known about the status of plants in Africa and South America than on other continents. Many of these species may disappear, too. A major review of the status of global biodiversity recently estimated that more than a million species, including 14% of plant and animal diversity, are threatened with extinction.

1. What caused the extinction of the Chile sandalwood tree?

A．Climate change.	B．The market demand.
C．Environmental pollution.	D．The decline of the habitat.

2. What do we know about the banded trinity?

A．It flowered without bearing seeds.

B．It disappeared during the 19th century.

C．It was a flowering plant without leaves.

D．It was a rare plant growing underground.

3. What can we infer about the plant species from the text?

A．Their current situation is more worrying.

B．About one plant species dies out every year.

C．More plant species will keep alive in the reserve.

D．They would be replaced by other new species soon.

4. In which section of the newspaper can we find the text?

A．Sports.

B．Nature.

C．Entertainment.

D．Figures.

2 . Animals can adapt quickly to survive unfavorable environmental conditions. Evidence is mounting to show that plants can, too. A paper published in the journal Trends in Plant Science details how plants are rapidly adapting to the effects of climate change, and how they are passing down these adaptations to their offspring(后代).

Plants are facing more environmental stresses than ever. For example, climate change is making winters shorter in many locations, and plants are responding. “Many plants require a minimum period of cold in order to set up their environmental clock to define their flowering time,” says Martinelli, a plant geneticist at the University of Florence. “As cold seasons shorten, plants have adapted to require shorter periods of cold to delay flowering. These mechanisms allow plants to avoid flowering in periods when they have fewer opportunities to reproduce.”

Because plants don’t have neural(神经的) networks, their memory is based entirely on cellular(细胞的),molecular(分子的),and biochemical networks. These networks make up what the researchers call somatic memory(体细胞记忆). “It allows plants to recognize the occurrence of a previous environmental condition and to react accordingly,” says Martinelli.

These somatic memories can then be passed to the plants’ offspring via epigenetics(表现遗传). “Several examples demonstrate the existence of molecular mechanisms modulating plant memory to environmental stresses and affecting the adaptation of offspring to these stresses,” says Martinelli.

Going forward, Martinelli hopes to understand even more about the genes that are being passed down. “We are particularly interested in decoding the epigenetic alphabet without changes in DNA sequence(序列),”he says. “This is especially important when we consider the rapid climate change, we observe today that every living organism, including plants, needs to quickly adapt to survive.”

1. What adaptations have plants made to shortened cold seasons?

A．They have shortened their flowering time.

B．They have got more chances to reproduce.

C．They have avoided flowering in cold seasons.

D．They have adjusted their environmental clock.

2. What can we learn about somatic memory?

A．It is entirely based on neural networks.

B．It can help the plants’ offspring to survive.

C．It can help relieve environmental stresses.

D．It disturbs the plants’ biochemical networks.

3. What does the underlined word “modulating” mean in paragraph 4?

A．Adjusting.	B．Treasuring.
C．Recording.	D．Sharing.

4. Which of the following is a suitable title for the text?

A．Plants are smart about flowering time

B．Plants can also adapt to climate change

C．Environmental stresses challenge plants

D．Mysteries of plant genes are to be unfolded

3 . 阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Hua Weiguang,     1     retired teacher from Tongliao, Inner Mongolia Autonomous Region, is a photography enthusiast.

A decade ago, the arrival of tree planters     2     (catch) Hua’s attention and the photos of the tree planters     3     (take) by Hua are evidence of the     4     (remark) transformation of the land. In those photos, hats, scarves and goggles, for the workers fighting desertification, are basic necessities to protect them     5     the wind and sand. There was no way to avoid the brutal summer heat in the land so the workers had to lie down on the ground or curl up in the narrow shade of their cars to cool off. And they also had to eat their lunch amid the blowing sands, taking in the small pieces of sand with their food.

“    6     we don’t fool the tree, it won’t fool you. You take it     7     (serious), and then it behaves in the same way to you. You put efforts to make it live, and the tree lives up to your     8     (expect),” the planters say.

China’s forest resources have increased by over 70 million hectares in the past decade,     9     (rank) first in the world. One tree after another, a green Great Wall has been built. Brush by brush, a green field     10     (paint) over the yellow sandy land up to now.

4 . Five Tasks for Your Winter Garden

As autumn has come, winter is on the way. When it finally arrives, it can be cold outside. However, even a blanket of snow doesn’t stop a keen gardener.     1    . Read on to find out some main tasks for winter.

Build New Beds

If you live in a more temperate area, you can start making new beds for your vegetable garden now. Raised beds are easy and relatively inexpensive if you have plenty of homemade fertilizers.     2    , you can usually pick it up quite cheap from the city landfill.

Tend to Apples and Pears

Winter is fit to prune(修剪) apple and pear trees. You can remove the damaged and diseased branches when the trees were dormant(休眠).     3    .

    4    

Frost covering can be put over cold hard vegetables before the temperature drops too far to help keep those plants happy in winter. Frost covering can be helpful for Brussels Sprouts, kale, winter cabbage and leeks if you live in milder climates.

Take Hardwood Cuttings(插条)

    5    . Some plants in the garden which do well with hardwood cuttings include elderberry and currants. Roses, buddleia (butterfly bush) and other shrubs also propagate by these types of cuttings.

A．Cover Crops

B．If you don’t have anything to made fertilizers

C．Here are plenty of jobs you can do in the garden

D．Many bare root trees can also be planted in winter

E．Even if homemade fertilizers will be bad as it is too cold

F．Plenty of leaves help keep some hardy plants from freezing

G．Winter is a great time to multiply plants by hardwood cuttings

5 . How to Prepare Houseplants for Fall

It would be easy to think that since houseplants live inside, they don't really experience seasons as their outdoor plants do.    1    However, it doesn't mean they don't know what's going on. They do. With that in mind, here is how to keep your plants happy when autumn comes.

    2    Check to be sure that they are not bringing any insects along with them. Examine both sides of leaves for insects, as well as the soil. Also, clear the top of the soil of dead leaves before taking them in.

Remove any dead or dying leaves. Find any yellowing or brown leaves.    3    For brown or yellowing leaves, you can just cut off the unhealthy part. To make a plant healthier, you can also trim（修剪）healthy leaves. Also, don't forget to save larger pieces to plant!

Be mindful of extreme temperatures. Hot or cold extremes can stress（使……紧张）plants out.    4    Make sure they are not by heaters. Similarly, make sure they are far from windows or doors that open to the outside.

Repot（移植）if needed. Spring is the best time to repot houseplants because that's when they begin to grow rapidly. But if any of your babies have had an active summer and are too small for their pot, now is a good time as well. Lift the plant out of the pot and check how the roots look.    5    

Be careful with watering. Over-watering is one of the most common houseplant mistakes. Unless you have especially thirsty species or a very dry home, wait at least a few days in between watering.

A．The plants under stress will die soon.

B．If they seem crowded, it is time to repot.

C．So be careful about where your plants are living.

D．Bring them in if they've been vacationing outside.

E．Pay attention to whether there are harmful insects.

F．It's true that they are provided more protection inside.

G．Cut off the leaves of these colors at the base or at the soil.

6 . In Australia, plenty of wild things can bite or sting(刺伤) you. Strangely enough, one of them is a tree. Now scientists have figured out what makes the tree’s sting so bad.

The rainforests of eastern Australia are home to a stinging tree known as Dendrocnide. Many people call it the gympie-gympie tree—a name given to the tree by native Australians. It’s covered with sharp, needle-like hairs that carry poison. If you touch a gympie-gympie tree, you won’t forget it anytime soon. The pain can stay with you for hours, days or weeks. In some cases, it’s been reported to stay for months.

Scientists have long looked for the source of this powerful sting. Now researchers at the University of Queensland have discovered what makes this stinging plant so painful. After carefully studying different kinds of gympie-gympie trees, the scientists were able to separate out different chemicals that the trees produce. This allowed them to identify a group of chemicals that they believed was responsible for the pain.

The researchers created artificial versions of these chemicals, which they call “gympietides”. Sure enough, when the scientists injected mice with gympietides, the mice licked(舔) at the places where they’d been injected, indicating that they hurt in those places. When the scientists studied the way gympietides were built, they found that they formed a knot-like shape. The shape makes the chemicals very stable,                                 which helps explain why the pain stays so long.

The knot-like shape of the gympietides was similar to the shape of poisons produced by poisonous spiders and cone snails. The scientists were surprised to see three very different kinds of life all using similar poisons. Spiders and cone snails carry poisons because they catch food by stinging other creatures. It’s not clear how stinging helps the gympie-gympie tree.

Though the tree’s sting may stop some animals from eating it, it doesn’t stop all animals. Beetles and pademelons (small relatives of the kangaroo) are able to eat the plant without trouble.

1. Why is a touch on the stinging tree unforgettable?

A．Because it has so unusual an appearance.	B．Because it is extremely rare in existence.
C．Because touching it creates a quite strange feeling.	D．Because the pain caused by it doesn’t go away quickly.

2. What do scientists fail to find out about the stinging tree?

A．How it produces poisons.	B．What poisons it produces.
C．How it benefits from the sting.	D．The consequences of its sting.

3. What does the text imply about the stinging tree?

A．It produces the same poisons as spiders.	B．Poisonous as it is, it also has natural enemies.
C．Animals are wise enough to stay away from it.	D．Only one chemical in it causes pain to the toucher.

4. What’s the best title for the text?

A．Scientists Discover Stinging Tree's Secret	B．Caution: Stinging Tree Can Bite and Poison You
C．Scientists Discover a Strange Species in Australia	D．Effective Ways to Avoid Being Hurt by Stinging Tree