A new study finds that plants communicate with one another to warn of danger.

We often consider plants as the furniture of the natural world. They don’t move; they don’t make sounds, they don’t seem to act on anything. But as is often the case, plants talk to each other all the time. And the language is chemical.

Over the years, scientists have reported that different types of plants, from trees to tomatoes, give out chemicals into the air to help neighboring plants. These chemical warnings can spread information about one plant’s disease or infestation(虫害), so other plants can protect themselves. But how plants receive and act on many of the information exactly is still mysterious.

In this week’s Science Magazine, researchers in Japan offered some explanations. They have found out one chemical message and traced it all the way from beginning to end.

The scientists looked at tomato plants infested by a common pest(害虫). To start out, they grew plants in two separate plastic spaces connected by a tube(管子). One plant was infested and placed upwind and the other was uninfested and placed downwind. The downwind plants were later exposed(暴露) to the pest. The results showed that plants near sick neighbors before were able to protect themselves better against the pest.

They found one chemical appeared more often in the exposed plants. The chemical is called HexVic. The scientists discovered where HexVic come from, and put it over healthy plants. Those plants were then able to produce HexVic. Researchers made sure that uninfested plants could fight off bugs and diseases. How do they know when to protect themselves? They are warned first by their friendly plant neighbors.

It is not a simple story, and it may be happening in more plant species than tomatoes. It may also be happening with more chemical signals that are still unknown to us. In a word, we know that plants not only communicate, but also look out for one another.

1The underlined “traced” in the fourth paragraph probably means _________ here.

A.      reported                     B. followed                C. doubted               D. developed

2.For scientists, which are the right steps to watch tomato plants infested by a pest?

①  Place the infested plant upwind.

②  Place the uninfested plant downwind.

③  Expose the downwind plants to the pest.

④  Grow plants in two separate plastic spaces connected by a tube.

A.      ③①②④               B. ①④③②                C. ④①②③                D. ④②①③

3.You can put the sentence “The researches also studied leaves from exposed plants and unexposed plants.” At the beginning of

A.      Paragraph 3        B. Paragraph 4          C. Paragraph 5         D. Paragraph 6

4.Which of the following can be the best title of this passage?

A.      Communicating Plants and Terrible Diseases

B.      Talking Plants and Friendly Warnings

C.     Protecting Plants and Clear Information

D.     Growing Plants and Mysterious Chemicals


完形填空 先通读下面的短文,掌握其大意,然后在每小题所给的A、B、C、D四个选项

When Karen found out that another baby was on the way. Like any good mother, she did what she could to help her 3-year-old son, Michael, 1 for it. They found out that it was going to be a girl, and day after day, night after night Michael 2 to his sister in Mommy's tummy(肚子)

Finally, Michael's little sister was born. But she was in 3 condition. They kept the baby girl in the ICU(重症监护室). The doctors told the parents, "There is very little hope." The little girl got 4 . Karen and her husband felt 5 . They planned to have a funeral for her.

Michael, 6 , kept begging his parents to let him see his sister. "I want to sing to her," he said. Kids were never 7 in ICU. Finally Karen decided to take Michael to his sister.

Michael looked at the 8 baby. And he began to sing. In the pure hearted voice of a 3-year-old, Michael sang: "You are my sunshine, my only sunshine, you make me happy when skies are grey." At once the little baby girl responded. Her pulse rate(脉搏) became 9 .

"Keep on singing, Michael," encouraged Karen with tears in her eyes. "You never know, dear. how much I 10 you. Please don't take my sunshine away." The baby girl's breath became smooth.

The next day - the very next day - the little girl was well enough to go home! The doctors called it a miracle. Karen called it a miracle of God's love!

1.A. look B. ask C. prepare D. wait

2.A. talked B. sang C. danced D. whispered

3.A. serious B. normal C. safe D. important

4.A. better B. thinner C. worse D. fatter

5. A. helpful B. homeless C. harmful D. helpless

6. A. otherwise B. moreover C. still D. however

7. A. allowed B. avoided C. treated D. punished

8. A. friendly B. lucky C. shy D. tiny

9.A. silent B. calm C. dangerous D. fast

10.A. know B. believe C. love D. change


阅读理解。

Lily is ten years old . One morning her good friend MeiMei says to her, “ Next Friday is my birthday. Would you like to come to my birthday party?” Lily says “ Yes, I would like to”

On Friday, Lily asks her mother, “ Can I go to MeiMei’s birthday party” “Yes, but you must be polite .and I want you to sing a song for your friend.” “Ok. Mum” Lily answers and goes to MeiMei’s home on foot. Then she buys a toy for MeiMei.

  At the party there are many children. Some are dancing . Some are talking. Some are playing cards. And Lily is singing an English song .There are some apples , oranges , bread , and a big birthday cake with eleven candles on it . The children sit around the cake. MeiMei makes a silent wish, and then blows the candles out in one breath. The child have a good time. Then Lily goes home by bus.

1. How old is MeiMei?

    A. ten           B. eleven           C. thirteen            D. twelve

2. What does Lily buy for MeiMei?

    A. apples        B. oranges          C. a toy              D. a big cake

3. What is Lily doing at the birthday party?xkb1.com

    A. singing        B. dancing         C. playing cards       D. talking

4. How does Lily go home

A. She walks home          B. She takes a car       

C. She rides a bike          D. She takes a bus

5. What is on the table?

A. An apple, two oranges and a birthday cake with candles on it 

B. apples , oranges, bread and a birthday cake with candles on it

C. some apples , bread and a birthday cake with candles on it

D. some apples , oranges  and a birthday cake with candles on it

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