Plants may not have eyes and ears，but they can recognize their siblings (兄弟姐妹)，and researchers at the University of Delaware have discovered how.The ID system lies in the roots and the chemical signals they secrete (分泌)．
Canadian researchers published that sea rocket，a common seashore plant，can recognize its siblings.Susan Dudley observed that when siblings are grown next to each other in the soil，they “play nice” and don’t send out more roots to compete.However，the moment one of the plants is thrown in with strangers，it begins competing with them by rapidly growing more roots to take up the water and mineral nutrients in the soil.
After reading Dudley’s study，Bais decided to find the method behind the sibling recognition.Working in his laboratory，Bais and his doctoral student Meredith Biedrzycki set up a study with wild populations of Arabidopsis thaliana.In a series of experiments，young seedlings were exposed to liquid media containing the root secretions from siblings，from strangers，or only their own secretions.The length of the longest lateral (侧面的) root was measured.The exposure of plants to the root secretions of strangers induced (引诱) greater lateral root formation than exposure of plants to sibling secretions.Strangers planted next to each other are often shorter，because so much of their energy is directed at root growth.Because siblings aren’t competing against each other，their roots are often much shallower (浅的)．
Biedrzycki did the painstaking laboratory research，observing more than 3,000 plants involved in the study every day for seven continuous days and documenting the root patterns.“Arabidopsis roots are nearly translucent (半透明的) when they are young and were also twisted when I removed them from plates，”Biedrzycki notes.“This manuscript (手稿) is very important for my research since the focus of my thesis project is understanding the biochemical ways behind root secretions.”
The research also may have implications for the home gardener.“Often we’ll put plants in the ground next to each other and when they don’t do well，we blame the local garden center where we bought them or we attribute their failure to a germ，”Bais says.“But maybe there’s more to it than that.”Which of the following would be the best title for this passage?
| A．A Great Biology Researcher |
| B．Plants Recognize Their Siblings |
| C．Plants’ Roots and Secretions |
| D．A Research on Plants |
What encouraged Bais to study the sibling recognition?
| A．Sea rocket. |
| B．Plants’ sensing system. |
| C．Biedrzycki’s thesis project. |
| D．Dudley’s study. |
What does the underlined word “painstaking” in Paragraph 4 probably mean?
| A．Important. | B．Adventurous. |
| C．Careful. | D．Hardworking. |
What can we infer from the last paragraph?
| A．The local garden center should be blamed when plants can’t grow well. |
| B．The local garden center often sells low quality seeds to customers. |
| C．Plants in the home garden can’t grow well because of the germ and seeds. |
| D．Competing against strangers，plants in the home garden can’t grow well. |
As a teenager in 1972, Bill Gates boasted that he would be a millionaire by the time he was 20. While he did not quite achieve that goal, only 15 years later, he was a millionaire. And by 1992, as head of the Microsoft company, he became the richest man in America with assets（资产）of nearly US $ 6.3 billion.
Born in Seattle, Washington on 28, October, 1956, Gates was named William Henry after his father and grandfather. From the beginning, he was an extremely energetic and intelligent child. He had read the entire world book encyclopedia（百科全书）by the age of nine. His favorite subjects at school were science and math and his favorite pastime was "thinking".
Gates first started to play with computers at the age of 13. Before long he became an expert at working the school's computer. After his graduation from secondary school, Gates was accepted by the three top universities in the USA-Princeton, Harvard and Yale. He chose Harvard and began classes there the next autunm, majoring maths. But he was still obsessed（占据心里）with computers and spent as much time in the computer laboratories as he did in the lecture halls.
By 1975, Gates and a partner, Paul Allen, had developed a software program called BASIC. This was not the first program ever created, but its inventors were the first to decide that people who wanted to use it should pay for it.
BASIC was a success because until it came along, there had been no efficient way of getting computers to carry out instructions. Although he had not completed his degree, Gates left university and went to work full time for the new company he had formed called Microsoft.
His next project was the software program that made him famous and very rich. It was called DOS, short for Disk Operating System, and it was purchased by IBM in 1980. Today it is the operating system used in more than 14 million personal computers around the world.
As chief executive officer（首席行政长官）of Microsoft, Gates is known as a bright man, but one who is not easily satisfied. He is quick to criticize his staff and hates to be questioned about decisions he has made. He was regarded as a loner and unfashionable boring computer nut until his marriage to Microsoft manager Melinda French on New Year's Day 1994. Yet to many people now, Gates, is a person who is, in spite of his great wealth, humble（谦恭）and ordinary. He spends his money carefully. He eats in fast food restaurants and flies economy class. And when praised for Microsoft's great success, he has been heard to say, "All we do is put software in a box and if people see it in the stores and like it, they buy it."When he was a teenager, Bill Gates wanted to be a ______.
| A．teacher | B．doctor | C．businessman | D．professor |
When Gates went to Harvard, he ______.
| A．was only interested in maths |
| B．spent most of his time in computer laboratories |
| C．developed the first computer software program |
| D．divided his time between his maths studies and the computer laboratories |
Before the development of BASIC, ______.
| A．no one was interested in computer software |
| B．software programs were not considered commercial projects |
| C．software programs were very expensive |
| D．no one wanted to pay for computer software |
When the writer says "He was regarded as a loner and unfashionable boring computer nut", he means ______.
| A．Bill was so strong-minded that no one could change his mind |
| B．The only thing that could interest Bill in his life was computer |
| C．Bill was such a boring young man that nobody would like to talk to him |
| D．Bill couldn't work out the boring computer programs |
Most people think that Bill Gates is ______.
| A．a crazy person | B．a person obsessed with making money |
| C．someone who spends money freely | D．a quite common, normal person |
Many people go to school for an education. They learn languages, history, politics, geography, physics, chemistry and mathematics. Others go to school to learn a skill so that they can make a living. School education is very important and useful. Yet, no one can learn everything from school. A teacher, no matter how much he knows, can not teach his students everything they want to know. The teacher’s job is to show his students how to learn. He teaches them how to read and how to think. So, much more is to be learned outside school by the students themselves.
It is always more important to know how to study by oneself than to memorize some facts or a formula(公式). It is actually quite easy to learn a certain fact in history or a formula in mathematics. But it is very difficult to use a formula in working out a math problem. Great scientists before us didn’t get everything from school .Their teachers only showed them the way. Edison did not even finish primary school. But they were all so successful. They invented so many things for mankind. The reason for their success is that they knew how to study. They read books that were not taught at school . They would ask many questions as they read. They did thousands of experiments. They worked hard all their lives, wasting not a single moment. Above all , they knew how to use their brain.To work out a math problem, you need to know __________.
| A．only a certain formula |
| B．how to memorize some facts |
| C．only some facts |
| D．the method to work it out |
Why were many scientists so successful?
| A．They received good education. |
| B．They were very clever. |
| C．They knew how to learn. |
| D．They learned lots of facts and formulas. |
How did great scientists study?
| A．They read a lot of books and asked many questions while reading. |
| B．They did thousands of experiments. |
| C．They always worked hard and never wasted time. |
| D．All of the above. |
One of the best-known American writers of children’s books is Alfred Strong, or Doctor Strong, as he is better known to readers everywhere. Now, an art show called “Doctor Strong From Then to Now” is travelling around the United States. The pictures and drawings show the history of Doctor Strong.
Doctor Strong first became famous almost fifty years ago when his first children’s book was published. Since then, he has written forty-five books that have sold more than one hundred million copies around the world.
Doctor Strong’s books are known for their easy use of words and colorful, hand-drawn pictures. These drawings bring life to his imaginary creatures. The Cat in the Hat, Horton the Elephant, The Grinch Who Stole Christmas, and hundreds of others.
The San Diego Museum, in California, organized the art show. It included about three hundred Doctor Strong’s original(最早的) drawings and some of his writings.
Most of Doctor Strong’s books, although written in a funny way, have serious messages. For example, in Mc Elligot’s Pool, he describes the danger of pollution. He discusses the arms race in The Butter Battle Book, written in 1984.
Doctor Strong is almost eighty-four years old now. He says he never planned to write stories just for children. He says he writes stories that interest people of all ages. He says he uses easy words so that everyone, even a child, can understand. Alfred Strong is a famous _______ in the United States.
| A．doctor | B．artist | C．writer | D．reader |
Doctor Strong first became famous in __________.
| A．his eighties when an art show was travelling around the United States |
| B．his fifties when his drawings and writings were published |
| C．1984 when his book Mc Elligot’s Pool was published |
| D．his thirties when his first book was published |
Doctor Strong’s books are very popular in America because __________.
| A．they are stories about animals such as cats, elephants and so on |
| B．they are written in easy words with colorful pictures |
| C．he organized the art show in California |
| D．they are written in a funny way |
His purpose in writing many such books is __________.
| A．to show his original pictures and drawings |
| B．to organize a special art show of his own |
| C．to make his readers laugh or smile when they read his books |
| D．not only to interest people but also to uncover some serious social problems |
Three high students become heroes after their act of saving a baby’s life.
Andrew Willis, 15, his brother Chris, 13, and friend Reece Galea, 14, were walking along Swallow Drive on their way to school on May 23, when Nicholle Price ran out of her house, shouting for help. Her six-month-old son Corey had swallowed (吞下) an earring （耳环） and the young mother couldn’t ring for help because something was wrong with her phone. The three teenagers rushed to the aid of Ms Price, called an ambulance (救护车), calmed her down and waited with her until the ambulance arrived before heading to school.
Ms Price, Corey and his grandmother Joyce Finnie visited the school last Thursday to thank the boys for their kind action. “It’s good to know that there are still some good people who will stop and help,” Ms Price said. “While I was shouting for help, a woman walking her dog went straight past, without stopping. I don’t know what would have happened if these boys had not stopped.”
The teenagers were shocked at the attention they received at school for their heroic act but admitted that the incident was nerve-racking(刺激神经的). “We heard her shouting so we knew something wasn’t right,” Andrew said. “We thought someone had died. It was scary （惊慌的） but we just did what we had to do.”
Just as proud as the boys’ parents is their principal, Tim McCallum.
After two days in hospital, Corey has now fully recovered. “He’s got two new teeth to show,” Ms Price said. “I have to keep a closer eye on him. He’s into everything now and grabs whatever he finds to put it straight into his mouth.” The three high students were _____ when a woman ran out of her house shouting for help.
| A．playing near the house |
| B．on their way to school |
| C．walking their dogs nearby |
| D．on their way back from school |
Ms Price spoke of a woman walking her dog without stopping to show _____.
| A．how dangerous the case was |
| B．how brave the three boys were |
| C．why the three teenagers’ action was heroic |
| D．how clever the three boys were |
The underlined sentence in the 4th paragraph probably means “_____”.
| A．they didn’t expect they would be given so much praise |
| B．they felt excited to have become so famous after the incident |
| C．they were supposed to receive so many prizes for their good deed |
| D．they were proud of the attention they received at school for their heroic deed |
Which would be the best title for this passage?
| A．How a baby was saved after swallowing an earring |
| B．Why the mother shouted for help |
| C．Baby life saved: teenage heroes earn high praise |
| D．A mother came to school to thank 3 teenagers |
Studies show that children who eat breakfast do better in school. It doesn’t take much further thought to know that adults will feel better and do better at work as well. Whether you work at home, on the farm, at the office, at school, or on the road, it is not a good idea to have no breakfast.
If we have no breakfast, we are likely to become tired when our brains and bodies run low on fuel (食物). By mid-morning, a lot of us grab a cup of coffee or eat a sugary candy bar to wake up again. This might work for a few minutes, but by lunch time we are hungry. Eating a good breakfast sets the tone for the rest of the day.
Having no breakfast is a popular way to lose weight, but not a smart one. Many people believe that they will lose weight if they have no meals, but that just isn’t true; the body expects to be refueled a few times a day, starting with a healthy breakfast.Eating breakfast is good for losing weight. In fact, people who eat breakfast are more likely to keep a healthy weight.
A healthy breakfast should have some protein (蛋白质) and some fiber (纤维). Protein can come from low fat meats, eggs, or beans. Fiber can be found in whole grains, vegetables and fruits. A good example of a healthy breakfast might be something simple like a hard boiled egg, an orange, and a bowl of whole grain cereal with low fat milk. Stay away from sugary foods and white bread because they are digested (消化) quickly and will leave you hungry and tired in several hours. Protein and fiber will keep you feeling full until lunch time. The first paragraph mainly tells us that ______.
| A．it is necessary to have a good breakfast every day |
| B．many adults are too busy to have breakfast every day |
| C．many adults go to work without having breakfast |
| D．many children go to school without breakfast |
According to the passage, we feel tired at work probably because __.
| A．we need to have a cup of coffee |
| B．we don’t have a good breakfast |
| C．our brains don’t work any longer |
| D．we don’t have enough sleep at night |
What does the underlined sentence in Paragraph 2 mean?
| A．Having a good breakfast can help you to finish your work. |
| B．Eating a good breakfast is enough for the whole day. |
| C．Breakfast is really the most important meal in a day. |
| D．You will be happier if you have a good breakfast. |
We can learn from the last paragraph that ______.
| A．it is healthy only to have beans and eggs for your breakfast |
| B．you mustn’t have meat for your breakfast |
| C．you should eat sugary foods if you feel hungry |
| D．you should eat something which has protein and fiber for breakfast |
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