Plants have family values,too,it seems,with new research sug?gesting they can recognize close relatives in order to work together.

An ability to tell family from strangers is well known in animals,allowing them to cooperate and share resources,but plants may pos?sess similar social skills,scientists believe.

Susan Dudley and Amanda File of McMaster University in Ontario? Canada,report they have demonstrated for the first time that plants can recognize their kin.

This suggests that plants,though lacking recognition and memory,are capable of complex social interactions.

"Plants have this kind of hidden but complicated social life," Dudley said.

The study found plants from the same species of beachdwelling wild flower grew aggressively alongside unrelated neighbours but were less competitive when they shared soil with their families.

Sea rocket,a North American species,showed stronger and healthier root growth when planted in pots with strangers than when raised with relatives from the same ma?ternal (母系的) family,the study found.

This is an example of kin selection,a behaviour common in animals in which closely related individuals take a group approach to succeeding in their environment,the researchers said.

Kin selection also applies to competition,because if family members compete less with each other,the group will do better overall. "Everywhere you look,plants are growing right up next to other plants," Dudley said. "Usually it's a case of each plant for itself. But sometimes those plants are related,and there are bene?fits to not wasting resources on being competitive,and there is not really a cost to not being competitive as long as your neighbour is also not being competitive."

Learning and memory appear to be important for kin recognition in animals,but this isn't an option for plants,she noted.

Some researchers speculate (猜测) that plants communicate through their roots,identifying themselves using tiny chemical signatures specific to each plant's family.

5. What's the main idea of the passage?

   A. Studies find plants can recognize and communicate with relatives.

   B. Kin selection is important for plants.

   C. Animals can recognize and memorize their relatives.

   D. Competition asks plants to recognize their relatives.

6. Which of the following is NOT right about animals' social skills?

   A. Animals can recognize and memorize their relatives.

   B. Animals' social skills are to cooperate and share resources.

   C. Animals' social skills can recognize close relatives to work together.

   D. Animals' social skills are no use at all.

7. Plants' kin selection is to         .

   A. grow well

   B. compete with other kinds of plants

   C. strengthen the relationship among siblings

   D. find which one is the best

8. From the passage,we learn that         .

   A. sea rocket is a South American species

   B. sea rocket grows aggressively alongside unrelated neighbours

   C. sea rocket grows aggressively alongside its siblings

   D. sea rocket is a kind of bush without flowers

 For a few years now,people have been expecting electronic textbooks to take off in a big way: they're cheaper than traditional textbooks,and seem like a natural progres?sion for students who have grown up playing and working with digital devices. Despite all that,traditional textbooks have prevailed―until now.

The game changer may be the iPad. Maclnnis is the founder of Inkling,a company that designs textbook soft?ware. He says the iPad has allowed for the reinvention of the textbook. He says that until now,etextbooks have basically just been bad imitations of their paper counter?parts.

Last year Reed College tried out the Kindle and this year they've been given free iPads to test. " The problem is that the Kindle is less interactive than a piece of paper,and the Kindle was so slow at highlighting and making notes that the students stopped reading them as scholarly texts and started reading them like novels," Alex Mont?gomery,a professor,said.

Senior Michael Crane and junior Rebecca Traber say that even though they've only had their iPads for a few weeks,they've already been pleasantly surprised.

"I thought it would just kind of be a fun toy," Crane says. "It makes it really easy to read articles for class. In fact,I read pretty much all my articles for all my classes on this now."

"I actually found it startlingly easy to make notes on," Traber says. "You just swipe your finger and you highlight. " Traber also has her doubts. " While I like reading on it better than reading on a laptop,in terms of creating anything—like writing papers or even e-mails-it's ridiculously hard," she says.  "I don't like the key?board at all."

Crane,Traber and Edwards may not know it yet,but they're all in the process of deciding what the classroom of the future will look like. They'll choose the device that works best for them—be it an iPad,a PC or a traditional textbook―and content providers will have to design soft?ware that works across each platform.

That's why digital textbooks will have to match the layout of their print counterparts.

20. The first paragraph tells us that         .

   A. textbooks are in an electronic style

   B. textbooks are still popular today

   C. e        textbooks will replace textbooks

   D. students in digital ages like textbooks

21. According to Maclnnis,the problem with the present etextbooks is '                 

   A. they are just a reinvention of textbooks

   B. they can't provide contents with simple concepts

   C. they just reflect the contents of textbooks

   D. they can't correctly display the contents of text?books 

22. What is the problem with Kindle?

   A. It can't enable readers to highlight something.

   B. It has no place for students to take notes.

   C. It doesn't provide students novels to read.

   D. It fails to interact with readers freely.

23. According to the text,iPad is suitable for         .

   A. writing   B. reading

   C. speaking   D. listening


A Whether at fast food places or fullserv?ice restaurants,kids who eat out are likely to consume more calories,sugar,fat and salt,researchers report.

They also noted that kids are eating out more,partic?ularly in fast food restaurants,which has helped drive the obesity epidemic among children and teenagers.

"Every day,about 40 per cent of American children eat at these restaurants ,”said lead researcher Lisa Powell. " We need policies that promote healthier food choices,rather than one that promotes unhealthy food choices. We also need to change the environment in the restaurant so that there won't be harmful effects on diet." This would include not offering free refills on soda and in?creasing healthier food choices,she explained.

A lot of the extra calories came from sodas,which kids and teenagers drink when they eat out,the research?ers said. This problem is particularly severe among poorer families. Eating at fast food restaurants is a way to get a lot of food inexpensively,Powell noted.

"Even with the general outcry that portions are too big,too high in sodium,fat and sugar,restaurants and fast food chains continue to increase the piece sizes of their foods," said Samantha Heller,an exercise physiologist.

"In addition,food companies encourage buying the bigsized products compared with the smaller piece”, Heller added,noting that a recent study reported that competition has encouraged the food industry to offer lar?gersize portions as a way to expand market share.

"It's no wonder kids are gaining weight and suffering from adult diseases such as high blood pressure and type 2        diabetes. We need to encourage people to cook at home more often and dismiss the myth that eating at home is more expensive than eating out”,she added.

"Planning menus ahead,making shopping lists and carving out time for homecooked meals will make eating at home easier,more enjoyable and healthier for the whole family," Heller said.

16. What does the underlined word "one" in Paragraph 3 refer to?

   A. The kid.

   B. The choice.

   C. The policy.

   D. The restaurant.

17. Why do the poor families eat out more often?

   A. Because they want their kids to have enough ener?gy.

   B. Because they are too busy to cook meals at home.

   C. Because they have to eat meals quickly for work.

   D. Because they can enjoy some food at a lower price.

18. How do food companies try to win more market share?

   A. By making food bigger in size. '   B. By making food more delicious.

   C. By making food more beautiful.

   D. By dividing food into pieces.

19. It is implied that Americans think      .

   A. eating at home will waste their time more

   B. cooking at home costs them more than eating out

   C. homecooked meals are much less delicious

   D. it is enjoyable for the whole family to eat out

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