7. Many factories and banks in some countries have closed down as a direct        (consequent) of the financial crisis going on in the USA.

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科目:高中英語 來源: 題型:

 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 (猜測(cè)) 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

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科目:高中英語 來源: 題型:


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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科目:高中英語 來源: 題型:

3. Many people believe that hunger is only a problem in the developing world. On the contrary,it is a problem all        the world.

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科目:高中英語 來源: 題型:

3. People who come to attend court hearings are always chosen at r        in order to be fair.

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科目:高中英語 來源: 題型:

10. How many times do you dine out per week        (平均) ?

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科目:高中英語 來源: 題型:

2. His sickness        (result) from eating too much.

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科目:高中英語 來源: 題型:

2.          average,there are 200 visitors to the exhibition every day.

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科目:高中英語 來源: 題型:

1. 有時(shí)我想知道我們是否能到達(dá)那里。

There were times when I wondered        we would get there.(whether…or…)

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