London—coffee protects mice from radiation and could get the same way in humans, according to Indian scientists.
Scientist at India’s Bhabha Atomic Research Center discovered that mice injected with caffeine (咖啡因)remained alive after high doses(剂量)of normally lethal radiation.
Although the study was limited to animals, Kachadillilli George, head of the research team, believes the findings could have implications (something suggested ) for humans .
“It does suggest that coffee might have some beneficial effects in protecting against radiation,” he told New Scientist magazine late last month.
George and his team injected 471 mice with caffeine and left them uncovered to 7.5 grays of gamma radiation(伽玛射线),enough to kill most mice. But 25 days later 70 percent of the mice that had received 80 milligrams(毫克)of caffeine per kilogram of body weight were still alive.
On the contrary all 196 mice that had been left uncovered to the same radiation but had not been given any caffeine died.George and his team drew the conclusion from .
| A．the magazine | B．their invention | C．the experiment | D．their experience |
From the news, we know can be protected from radiation.
| A．both mice and humans | B．only mice |
| C．only humans | D．neither humans nor mice |
From paragraph 5, we know 30 percent of the mice died 25 days later. The reason was probably that .
| A．these mice had been given only 80 milligrams of caffeine |
| B．these mice hadn’t been injected with caffeine |
| C．these mice were very big and strong |
| D．these mice hadn’t been given enough caffeine |
Which is the best title of the article?
| A．Human and Mice | B．New Radiation Defense—Coffee |
| C．Deadly Radiation—Gamma Radiation | D．Mice Died of Caffeine |
In paragraph 2,the underlined word “ lethal ”means .
| A．causing death | B．lively | C．exciting | D．rich |
As you grow older, you’ll be faced with some challenging decisions—like whether to cut class or try cigarettes. Making decisions on your own is hard enough, but when other people get involved and try to pressure you one way or another it can be even harder. People who are your age, like your classmates, are called peers. When they try to influence how you act, to get you to do something, it’s called peer pressure.
Peers can have a positive influence on each other. Maybe another student in your science class taught you an easy way to remember the planets in the solar system. Maybe you got others excited about your new favorite book, and now everyone’s reading it. These are examples of how peers positively influence each other.
Sometimes peers influence each other in negative ways. For example, a few kids in school might try to get you to cut class with them; your soccer friend might try to convince you to be mean to another player and never pass him the ball.
It is tough to be the only one who says “no” to peer pressure, but you can do it. Paying attention to your own feelings and beliefs about what is right and wrong can help you know the right thing to do.
You’ve probably had a parent or teacher advising you to “choose your friends wisely.” Peer pressure is a big reason why they say this. If you choose friends who don’t cut class, smoke cigarettes, or lie to their parents, then you probably won’t do these things either, even if other kids do.
If you continue to face peer pressure and you’re finding it difficult to handle, talk to someone you trust. Don’t feel guilty if you’ve made a mistake or two.For whom is the passage most probably written?
| A．Parents. | B．Teachers. |
| C．Students. | D．Doctors. |
In the last three paragraphs, the author mainly_____.
| A．explains why friendship is so important |
| B．shows how to make more good friends |
| C．discusses how peers influence us |
| D．gives advice on how to deal with peer pressure |
Which of following may help handle peer pressure?
| A．Spending more time with classmates. |
| B．Taking up more relaxing hobbies. |
| C．Choosing friends with no bad habits. |
| D．Helping others who are in trouble. |
What is the topic of the passage?
| A．Friendship. | B．Making decisions |
| C．Self-confidence | D．Peer pressure |
I have a friend named Monty Roberts who owns a horse ranch in San Ysidro. He has let me use his house to put on fund-raising events to raise money for youth at risk programs．
The last time I was there he introduced me by saying, "I want to tell you why I let Jack use my house.” It all goes back to a story about a young man who was the son of a horse trainer who would go from stable to stable, race track to race track, farm to farm and ranch to ranch, training horses. As a result, the boy's high school career was continually interrupted. When he was a senior, he was asked to write a paper about what he wanted to be and do when he grew up.”
That night he wrote a seven-page paper describing his goal of someday owning a horse ranch．He wrote about his dream in great detail and he even drew a diagram of a 200-acre ranch, showing the location of all the buildings, the stables and the track. Then he drew a detailed floor plan for a 4,000-square-foot house that would sit on a 200-acre dream ranch．”
He put a great deal of his heart into the project and the next day he handed it in to his teacher. Two days later he received his paper back. On the front page was a large red F with a note that read, "See me after class.”Why can the writer use Roberts's house to raise money for youth at risk programs?
| A．Because they are good friends. |
| B．Because the youth has the same dream as Monty Roberts. |
| C．Because Monty Roberts has a poor childhood. |
| D．Because Monty Roberts like to help youth． |
What do you think of Monty Koberts' goal of a horse ranch at that time?
| A．romantic | B．real |
| C．dream | D．false |
What would happen after the teacher gave a note "See me after class.”?
| A．Monty Roberts got very angry at this. |
| B．The teacher would criticize him. |
| C．The teacher wanted to tell him that his dream would come true． |
| D．The teacher would encourage him. |
Mars( 火星) appears to be flowing with small streams of salty water, at least in the summer, scientists reported Monday. "It suggests that. it would be possible for there to be life today on Mars," NASA's science mission chief, John Grunsfeld, said at a news conference on September 28, 2015.
The streams are about 12 to 15 feet wide and 300 feet or more long, scientists said. "What we're dealing with is wet soil. thin layers of wet soil, not standing water," said Aifred McEwen of the University of Arizona at Tueson ! the principal scientist for the Mars Reconnaissance Orbiter's high-resolution imaging experiment.
Because liquid water is essential to life, the findings could have major implications for the possibility of Martian life. The researchers said further exploration is needed to determine whether microscopic life exists on the planet.
The presence of liquid water could also make life easier for astronauts visiting or living on Mars. Water could be used for drinking and for creating oxygen and rocket fuel. NASA's goal is to send humans there in the 2030s.
The evidence of flowing water consists largely of dark, narrow streaks(条痕) on the surface that tend to appear and grow during the warmest Martian months and fade the rest of the year.
Mars is extremely cold even in summer, and the streaks are in places where the temperature is as low as minus 10 degrees Fahrenheit. But salt can lower the freezing point of water and melt ice.
The source(源头) of the water is a mystery. Scientists noted it could be melting ice. It could be an underground aquifer, which is rock or sand that can hold water. It is possibly water vapor from the thin Martian atmosphere, Or it may be a combination.
Michael Meyer, lead scientist for NASA's Mars exploration program, said the only definitive way for now to determine whether there's life on Mars is to collect rocks and soil for analysis on Earth - something a U. S. lander set for lift-off in 2020 will do.
What would be the best title for the text?
A Streams of Water Spotted on Mars
B. Astronauts will Land on Mars
C. NASA's Mars Exploration Program
D. A Breakthrough in the Exploration of Mars
According to John Grunsfeld, there seems to be on Mars.
| A．salty water |
| B．standing water |
| C．rocket fuel |
| D．human beings |
Scientists are uncertain about the of the water on Mars.
| A．state |
| B．source |
| C．temperature |
| D．taste |
What matters to the existence of liquid water on Mars?
| A．The distance from the sun. |
| B．The favorable climate. |
| C．The gravity of the earth |
| D．The salt in it． |
We all know what a brain is. A doctor will tell you that the brain is the organ of the body in the head. It controls our body's functions, movements, emotions and thoughts. But a brain can mean so much more.
A brain can also simply be a smart person, If a person is called brainy, she is smart and intelligent. If a family has many children but one of them is super smart, you could say, "She's the brains in the family. " And if you are the brains behind something you are responsible for developing or organizing something. For example, Bill Gates is the brains behind Microsoft.
Brain trust is a group of experts who give advice. Word experts say the phrase"brain trust" became popular when Franklin D. Roosevelt first ran for president in 1932, Several professors gave him advice on social and political issues facing the U. S.These professors were called his "brain trust. "
These ways we use the word "brain" all make sense. But other ways we use the word are not so easy to understand. For example, to understand the next brain expression, you first need to know the word“drain." As a verb to drain means to remove something by letting it flow away. So a brain drain may sound like a disease where the brain flows out the ears. But, brain drain is when a country's most educated people leave their countries to live in another. The brains are,sort of,draining out of the country.
However,if people are responsible for a great idea,you could say they brainstormed it. Here,brainstorm is not an act of weather. It is a process of thinking creatively about a complex topic. For example, business leaders may use brainstorming to create new products, and government leaders may brainstorm to solve problems.
If people are brainwashed, it does not mean their brains are nice and clean. To brainwash means to make someone accept new beliefs by using repeated pressure in a forceful or tricky way. Keep in mind that brainwash is never used in a positive way.
According to the text, if you're the CEO of Bai Du you can be called________.
| A．the brains behind Bai Du |
| B．Bai Du's brain trust |
| C．the brain drain of Bai Du |
| D．the organ of Bai Du |
Why did Roosevelt successfully win the election?
| A．Because he was smart at giving advice. |
| B．Because word experts were popular. |
| C．Because he got his brain trust. |
| D．Because he was the brains behind America. |
Which of the following expression is always used in a negative way?
| A．Brain trust | B．Brain drain |
| C．Brainstorm | D．Brainwash |
Giving Back
Fair Way
The Westborough High School golf team had taken the official photos with the state prize. The other teams, disappointed, were on the bus heading home. And the Westborough instructor Greg Rota noticed something wrong on one of the score cards. A 9 had been recorded as a 7. They were not the state prize winner; Wobum High had won. "No one would have known, said Wobum's instructor, Bob Doran. For Rota, it wasn’t a difficult decision: “The prize wasn’t ours to take.”
Coin Stars
"College students are lazy. but they also want to help," says University of Pennsylvania graduate. Dan Hork. So she made it easy, placing cups in rooms where students could leave their spare coins, and handing out cups to first-year students to keep in their rooms. Her "Change for Change" effort has collected$40,000 for charities, which were decided upon by students .
Never Forgotten
A school in Massachusetts received a $ 9. 5 million check from Jacques LeBermuth. But it took officials several days of digging to discover his connection to the school. Records showed the LeBermuth came from Belgium and studied in the school in the1920s. When his family fell on hard times, he was offered free room and board.LeBermuth became a trader, owned shares of AT&T and lived off the earnings until he died , at age 89.
What did Greg Rota probably do in the end?
| A．Returned the prize to the organizer, |
| B．Apologized to Wobum High School. |
| C．Took photos of the state prize. |
| D．Had a meeting with Doran |
Greg Rota's decision shows that he was .
| A．polite | B．honest |
| C．careful | D．friendly |
The underlined word "Change" in the second paragraph means__________.
| A． Idea | B． Decision | C． Cups | D．Coins |
Jacques LeBermuth gave the money to the school because _________.
| A．the school asked for it |
| B．he had no need for that much money |
| C．the school had helped him in the past |
| D．he wanted to be remembered by the students |
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