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    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.
    小题1:The underlined “traced” in the fourth paragraph probably means _________ here.
    A．reportedB．followed
    C．doubtedD．developed
    小题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．③①②④B．①④③②
    C．④①②③D．④②①③
    小题3:You can put the sentence “The researches also studied leaves from exposed plants and unexposed plants.” At the beginning of
    A．Paragraph 3B．Paragraph 4
    C．Paragraph 5D．Paragraph 6
    小题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

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    Channel 1

    6：00 English Today

    6：30 Sports News

    6：45 Healthy Living

    7：00 News

    7：35 Tell it like it is

    8：15 Harry Potter

    Channel 2

    6：15 Culture China

    6：45 Animal World

    7：20 Popular Music

    7：40 Brothers

    8：35 Chinese Cooking

    9：00 English Study

    （   ）1．Jim likes music．He can watch TV at_______．

    A．6：00                  B．7：35                  C．7：20                    D．7：00

    （   ）2．It’s 8：35．Jim’s mother is watching_______ on Channel 2．

    A．Culture China                                          B．Animal World

    C．TV play                                                    D．Chinese Cooking

    （   ）3．Harry Potter is at_______．

    A．8：15 on Channel 1                                 B．8：15 on Channel 2

    C．7：40 on Channel 1                                   D．7：40 on Channel 2

    （   ）4．Tom watches TV at 6：00 and 9：00．He may learn_______．

    A．math                   B．Chinese                C．English                  D．music

    （   ）5．David loves news．He can watch TV_______．

    A．at 6：30 and 7：00                                  B．at 7：00 and 9：00

    C．at 6：45 and 8：15                                    D．at 6：15 and 7：40

    查看答案和解析>>

    Most people work or study from Monday to Friday. The weekend is usually a time of rest. But today's Chinese teenagers can hardly rest during the weekends.
    According to a survey, 24% of the Grade 8 students in Beijing have classes at the weekend. Over 40% of the middle school students have less than eight hours’ sleep each night because of study.
    And this isn't only in Beijing. Ji Chunying is a Grade 9 student in Guangzhou. The 14-year-old girl has to get up at 6:45 am on Saturday. Then she has a whole day of classes. On Sunday, she goes to extra classes for math and physics.
    But Ji doesn't complain. She says her classmates all work very hard.
    Finding time to have fun

    Zhao Yang, 13, is from Dalian, Liaoning. As a Grade 8 student, Zhao's weekend is less busy. But he still spends Saturday in school. On Sunday, after finishing homework, he plays basketball. "I feel happy because I still have time to do the things I like," he said.
    Some students are much luckier. They don't have to go to school on the weekend.
    Ding Yi, a Grade 8 student from Laiwu, Shandong, is one of them. And she's a top student.
    During the weekend, Ding usually gets up at 8 am. Then she spends some time doing homework. After that she is free to go shopping or watch TV.
    Ding said her mother once wanted her to try extra classes. But when they asked Ding's teacher about it, the teacher said it was unnecessary.
    "My teacher said I don't need to push myself too much. Learning well at school is enough," Ding said. "I feel pretty lucky."
    【小题1】Over 40% of the middle school students have less than eight hours sleep each night because of ___________.

    A．playing computer games
    B．playing with friends
    C．busy study
    D．watching TV
    【小题2】How many students are mentioned in this passage?
    A．2.B．3.C．4.D．5.
    【小题3】We can learn from the passage that ___________.
    A．Some middle school students can enjoy their weekend.
    B．All the students in China are busy studying on the weekend.
    C．Every student in China has to go to extra classes on the weekend.
    D．All the students complain about their busy weekend.
    【小题4】The above text may be a _______.
    A．a story of scienceB．school notice
    C．short playD．news report

    查看答案和解析>>

    Most people work or study from Monday to Friday. The weekend is usually a time of rest. But today's Chinese teenagers can hardly rest during the weekends.

    According to a survey, 24% of the Grade 8 students in Beijing have classes at the weekend. Over 40% of the middle school students have less than eight hours’ sleep each night because of study.

    And this isn't only in Beijing. Ji Chunying is a Grade 9 student in Guangzhou. The 14-year-old girl has to get up at 6:45 am on Saturday. Then she has a whole day of classes. On Sunday, she goes to extra classes for math and physics.

    But Ji doesn't complain. She says her classmates all work very hard.

    Finding time to have fun

    Zhao Yang, 13, is from Dalian, Liaoning. As a Grade 8 student, Zhao's weekend is less busy. But he still spends Saturday in school. On Sunday, after finishing homework, he plays basketball. "I feel happy because I still have time to do the things I like," he said.

    Some students are much luckier. They don't have to go to school on the weekend.

    Ding Yi, a Grade 8 student from Laiwu, Shandong, is one of them. And she's a top student.

    During the weekend, Ding usually gets up at 8 am. Then she spends some time doing homework. After that she is free to go shopping or watch TV.

    Ding said her mother once wanted her to try extra classes. But when they asked Ding's teacher about it, the teacher said it was unnecessary.

    "My teacher said I don't need to push myself too much. Learning well at school is enough," Ding said. "I feel pretty lucky."

    1.Over 40% of the middle school students have less than eight hours sleep each night because of ___________.

    A．playing computer games

    B．playing with friends

    C．busy study

    D．watching TV

    2.How many students are mentioned in this passage?

    A．2.               B．3.                C．4.               D．5.

    3.We can learn from the passage that ___________.

    A．Some middle school students can enjoy their weekend.

    B．All the students in China are busy studying on the weekend.

    C．Every student in China has to go to extra classes on the weekend.

    D．All the students complain about their busy weekend.

    4.The above text may be a _______.

    A．a story of science                       B．school notice

    C．short play                             D．news report

     

    查看答案和解析>>

    Most people work or study from Monday to Friday. The weekend is usually a time of rest. But today's Chinese teenagers can hardly rest during the weekends.
    According to a survey, 24% of the Grade 8 students in Beijing have classes at the weekend. Over 40% of the middle school students have less than eight hours’ sleep each night because of study.
    And this isn't only in Beijing. Ji Chunying is a Grade 9 student in Guangzhou. The 14-year-old girl has to get up at 6:45 am on Saturday. Then she has a whole day of classes. On Sunday, she goes to extra classes for math and physics.
    But Ji doesn't complain. She says her classmates all work very hard.
    Finding time to have fun

    Zhao Yang, 13, is from Dalian, Liaoning. As a Grade 8 student, Zhao's weekend is less busy. But he still spends Saturday in school. On Sunday, after finishing homework, he plays basketball. "I feel happy because I still have time to do the things I like," he said.
    Some students are much luckier. They don't have to go to school on the weekend.
    Ding Yi, a Grade 8 student from Laiwu, Shandong, is one of them. And she's a top student.
    During the weekend, Ding usually gets up at 8 am. Then she spends some time doing homework. After that she is free to go shopping or watch TV.
    Ding said her mother once wanted her to try extra classes. But when they asked Ding's teacher about it, the teacher said it was unnecessary.
    "My teacher said I don't need to push myself too much. Learning well at school is enough," Ding said. "I feel pretty lucky."
    小题1:Over 40% of the middle school students have less than eight hours sleep each night because of ___________.
    A．playing computer games
    B．playing with friends
    C．busy study
    D．watching TV
    小题2:How many students are mentioned in this passage?
    A．2.B．3.C．4.D．5.
    小题3:We can learn from the passage that ___________.
    A．Some middle school students can enjoy their weekend.
    B．All the students in China are busy studying on the weekend.
    C．Every student in China has to go to extra classes on the weekend.
    D．All the students complain about their busy weekend.
    小题4:The above text may be a _______.
    A．a story of scienceB．school notice
    C．short playD．news report

    查看答案和解析>>


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