For the first time, researchers have discovered that some plants can kill insects in order to get additional nutrients. New research shows that they catch and kill small insects with their own sticky hairs near the roots and then absorb nutrients through their roots when the insects are killed and fall to the ground.

Professor Mark Chase, of Kew and Queen Mary, University of London, said: “The cultivated (改良的) tomatoes and potatoes still have the hairs. Tomatoes in particular are covered with these sticky hairs. They do trap small insects on a regular basis. They do kill insects.”

The number of these carnivorous plants is thought to have came up to 50 percent and many of them have until now been wrongly regarded as among the most harmless plants. Among them are species of petunia（矮牽牛）, some special tobacco plants and cabbages, some varieties of potatoes and tomatoes, etc. Researchers at Royal Botanical Gardens Kew, which carried out the study, now believe there are hundreds more killer plants than previously realized.

It is thought that the technique was developed in the wild to get necessary nutrients in poor quality soil – and even various plants grown in your vegetable garden still have the ability.

The researchers, publishing their finding in the Botanical Journal of the Linnean Society, said: “We may be surrounded by many more murderous plants than we think.” “We are accustomed to thinking of plants as being immobile and harmless, and there is something deeply frightening about the thought of meat-eating plants," they added.

1.Tomatoes and potatoes kill insects to _____.

A. get more sticky hairs

B. make themselves grow better

C. make their roots stronger

D. avoid falling down to the ground

2.The word “carnivorous” in Paragraph 3 most probably means _____.

A. fast-growing

B. harmless

C. insect-killing

D. nutritious

3.The insect-killing technique of vegetables is developed most probably through _____.

A. evolution of species

B. helps from other garden plants

C. artificial cultivation

D. nutrients preserved in rich soil

4.The text is probably taken from _____.

A. a student book

B. a science fiction

C. a scientific repot

D. a bulletin board

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House Sitting

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E

Manners nowadays in big cities like London are particularly non-existent. It’s nothing for a big, strong schoolboy to elbow an elderly woman aside in the dash for the last remaining seat on the tube or bus, much less stand up and offer his seat to her.

This question of giving up seats in public transport is much argued by young men, who say that, since women have claimed equality, they no longer deserve to be treated with courtesy(謙恭有禮) and that those who go out to work should take their turn in the rat race like anyone else. Women have never claimed to be physically as strong as men. Even if it’s not agreed, however, that young men should stand up for older women, the fact remains that courtesy should be shown to the old, the sick and the burdened. Are we really so lost to all ideals of unselfishness that we can sit there indifferently reading the paper or a book, saying to ourselves “ First come, first served”, while a gray-haired woman, a mother with a young child or a cripple stands? Yet this is too often seen.

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Many people write to newspaper and magazines to express their opinions. Letters to the editor must carry the writer’s full name, address and telephone number, although the information is not necessary for publication. This requirement to provide personal particulars is a clear indication that writers are held responsible for what they say. When a writer wants his voice heard, he needs to claim ownership of his voice. Responsibility is the name of the game.

“People today prefer living together to putting their signatures on a marriage certificate because they refuse to accept responsibility for the relationship,” said social worker Ken Yip, “and this is what is causing a lot of family problems.” When we sign a paper, for example, a business contract or a bank document, the signature is a seal of consent, an agreement to take the matter seriously. Most governments and many organizations will not process written complaints if they do not bear the writer’s signature. The absence of a signature, they explain, tells us that the writer cannot be too serious and therefore does not deserve a reply.

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D. Names are required to indicate writers’ responsibility for what they say.

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C. afraid of an accusation

D. ready for involvement

4.The passage is mainly about _______.

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C. signature and responsibility

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