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Can people change their skin colour without suffering like pop king Michael Jackson? Perhaps yes.Scientists have found the gene that determines skin colour.
The gene comes in two versions, one of which is found in 99 per cent of Europeans.The other is found in 93 to 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the colour of a dark-striped zebrafish to uniform gold by inserting a version of the pigment(色素) gene into a young fish.As with humans, zebrafish skin colour is determined by pigment cells, which contain melanosomes(黑色素).The number, size and darkness of melanosomes per pigment cell determines skin colour.
It appears that, like the golden zebrafish, light-skinned Europeans also have a mutation(变异) in the gene for melanosome production.This results in less pigmented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in human and zebrafish genes.
Humans acquired dark skin in Africa about 1.5 million years ago to protect bodies from ultra-violet rays(紫外线) of the sun, which can cause skin cancer.
But when modern humans leave Africa to live in northern latitudes, they need more sunlight on their skin to produce vitamin D.So the related gene changes, according to Cheng.
Asians have the same version of the gene as Africans, so they probably acquired their light skin through the action of some other gene that affects skin colour, said Cheng.
The new discovery could lead to medical treatments for skin cancer.It also could lead to research into ways to change skin colour without damaging it like chemical treatment did on Michael Jackson.
What is the main idea of the passage?

A.People can’t change their skin colour without any pain.
B.The new discovery helped find ways to change skin colour safely.
C.Pop king Michael Jackson often changed his skin colour as he liked.
D.Scientists have found out that people’s skin colour is determined by the gene.

It can be inferred from the passage that ________.

A.nowadays changing the skin colour with the chemical treatment has bad effect
B.Europeans and Africans have the same genes
C.the new discovery could help to find medical treatments for skin cancer
D.there are two kinds of skin genes

Scientists have done an experiment on a dark-striped zebra fish in order to ________.

A.find the different genes of humans
B.prove the humans’ skin colour is determined by the pigment gene
C.find out the reason why the Africans’ skin colour is dark
D.find out the ways of changing people’s skin colour

Which of the following statements is TRUE?

A.Michael Jackson died of skin damage caused by chemical treatment.
B.American blacks produce more vitamin D with their skin than others.
C.The gene determining skin colour exists widely in whites, blacks and Asians.
D.The melanosomes in the skin of blacks usually cause skin cancer more often.
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BRITAIN is a popular tourist place.But tours of the country have advantages and disadvantages.
GOOD NEWS
Free museums.No charge for outstanding collections of art and antiquities(文物).
Pop music.Britain is the only country to compare with the US on this score.
Black cabs.London taxi drivers know where they are going even if there are never
enough of them at weekends or night.
Choice of food.Visitors can find everything from Ethiopian to Swedish restaurants.
Fashion.Not only do fashion junkies love deeply and respect highly brand names such as Vivienne Westwood, Alexander McQueen; street styles are justly loved, too.
BAD NEWS
Poor service.“It’s part of the image of the place.People can dine out on the rudeness they have experienced,” says Professor Tony Seaton, of Luton University’s International Tourism Research Center.
Poor public transport.Trains and buses are promised to defeat the keenest tourists, although the overcrowded London tube is inexplicably (难以理解的) popular.
Rain.Still in the number one complaint.
No air-conditioning.So that even splendidly hot summers become as unbearable as the downpours.
Overpriced hotels.The only European country with a higher rate of tax on hotel rooms is Denmark.
Licensing hours.Alcohol (酒) is in short supply after 11 p.m. even in “24-hour cities”.
What do tourists complain most?

A.Poor service. B.Poor public transport.
C.Rain. D.Overpriced hotels.

What do we learn about pop music in Britain and the US through this passage?

A.Pop music in Britain is better than that in the US.
B.Pop music in Britain is as good as that in the US.
C.Pop music in Britain is worse than that in the US.
D.Pop music in Britain is quite different from that in the US.

When are people not able to get alcohol?

A.At 12: 00 p.m. B.At 10: 00 p.m.
C.At 11: 00 p.m. D.At 9: 00 p.m.

Which of the following is True according to the passage?

A.You have to pay to visit the museums
B.It’s very cheap to travel by taxi there.
C.You cannot find Chinese food there
D.The public transport is poor there.

For years I wanted a flower garden.But then we had Matthew.And Marvin.And the twins, Alisa and Alan.And then Helen.Five children.I was too busy raising them to grow a garden.
Money was tight, as well as time.Often when my children were little, one of them would want something that cost too much, and I' d have to say, “Do you see a money tree outside? Money doesn't grow on trees, you now.”
Finally, all five got through high school and college and were off on their own.
One spring morning, on Mother's Day, I was working in my kitchen.Suddenly, I realized that cars were tooting their horns as they drove by.I looked out the window and there was a new tree, planted right in my yard.I thought it must be a weeping willow, because I saw things blowing around on all its branches.Then I put my glasses on-and I couldn't believe what I saw.
There was a money tree in my yard!
I went outside to look.It was true! There were dollar bills, one hundred of them, taped all over that tree.Think of' all the garden flowers I could buy with one hundred dollars! There was also a note attached: ‘‘IOU eight hours of digging time.Love, Marvin."
Marvin kept his promise, too.He dug up a nice ten-by-fifteen foot bed for me And my other children bought me tools, ornaments , a trellis(格架), a sunflower stepping stone and gardening books.
That was three years ago.My garden's now very pretty, just like I wanted.When I go out and tend my flowers, I don't seem to miss my children as much as I once did.I feel like they're right there with me.
I'm still not sure that money grows on trees.But I know love does!
Why did the mother say "Money doesn't grow on trees"?.

A.She wanted them not to spend extra money
B.She was too sad to say anything else
C.She told them a truth on money
D.she just played a joke with them

What do we know about the mother according to the text?

A.She is a bad-tempered woman
B.She believes money can grow on a tree now
C.She is a writer
D.She is hard-working in housekeeping

What can be inferred from the text?

A.The author raised five children
B.The money tree was a Mother Day's gift
C.It cost Marvin eight hours to dug up the bed
D.Children planted a weeping willow in the yard

Which of the following would be the best title for the text? ___

A.My Money Tree B.The Garden of My Children
C.Mother's Love D.Marvin's Promise

Many a young person tells me he wants to be a writer. I always encourage such people, but I also explain that there’s a big difference between “being a writer” and writing. In most cases these people are dreaming of wealth and fame, not the long hours alone as a typewriter. “You’ve got to want to write,” I say to them, “not want to be a writer.”
The reality is that writing is a lonely, private and poor-paying affair. For every writer kissed by fortune there are thousands more whose wish is never rewarded. When I left a 20-year career in the U.S, Coast Guard to become a freelance writer(自由撰稿者), I had no hope at all. What I did have was a friend who found me my room in a New York apartment building. It didn’t even matter that it was cold and had no bathroom. I immediately bought a used typewriter and felt like a real writer.
After a year or so, however, I still hadn’t got a break and began to doubt myself. It was so hard to sell a story that barely made enough to eat. But I knew I wanted to write. I had dreamed about it for years. I wasn’t going to be one of those people who die wondering. What if? I would keep putting my dream to the test even though it meant living with uncertainty and fear of failure. This is the shadow land of hope, and anyone with a dream must learn to live there.
The writer wrote the passage to ________.

A.warn young people of the hardships that a successful writer has to experience
B.advise young people to give up their ideas of becoming a professional writer
C.show young people it’s unrealistic for a writer to dream of wealth and fame
D.encourage young people to gain a writing career

What can be concluded from the passage?

A.Real writers often find their works interesting and rewarding.
B.A writer’s success depends on luck rather than on effort.
C.Famous writers usually live in poverty and loneliness.
D.The chances for a writer to become successful are small.

The underlined part “people who die wondering. What if?” refers to “those _______.”

A.who think too much of the dark side of life
B.who regret giving up their careers halfway
C.who think a lot without making a decision
D.who are full of imaginations even upon death

What is the best title of the passage?

A.how to be a writer B.how to earn fame
C.how to write well D.how to keep dreaming

Bill Gates was born on October 28th, 1955. He and his two sisters grew up in Seattle. Their father, William H. Gates II, was a Seattle lawyer. Mary Gates, their late mother, was a school teacher.
Gates attended public elementary school before moving on to the private Lakeside School in North Seattle. It was at Lakeside that Gates began his career in personal computer soft ware, programming computers at age 13.
In 1973, Gates entered Harvard University as a freshman, where he lived down the hall from Steve Ballmer, who is now Microsoft's president. While at Harvard, Gates developed a version (版本) of the programming language BASIC for the first microcomputer---the MITS Astair. In his junior year, Gates dropped out of Harvard to devote his energies full-time to Microsoft, a company he had started in 1975 with his boyhood friend Paul Allen. Guided by a belief that the personal computer would be a valuable tool on every office desk-top and in every home, they began developing software for personal computers.
Gates' foresight has led to the success of Microsoft and the software industry. He plays an important role in the technical development of new products. Much of his time is devoted to meeting with customers and staying in touch with Microsoft employees around the world through e-mail.
In the dozen years since Microsoft went public, Gates has donated more than $ 800 million to charities, including $ 200 million to the Gates Library Foundation to help libraries in North America make use of new technologies and the Information Age.
Where did Bill Gates begin his career in personal computer software?

A.At public elementary school. B.At the private Lakeside School.
C.At Harvard University. D.At Microsoft Company.

Why did he drop out of Harvard?

A.To change school. B.To spend all his energies to Microsoft.
C.To find a full-time job. D.To earn money.

How does Gates spend much of his time?

A.Meeting with people.
B.Travelling around the world.
C.E-mailing some friends.
D.Meeting with customers and e-mailing Microsoft employees.

What does the underlined word “donated” in the last paragraph mean?

A.gave. B.earned. C.made. D.received.

The eight airlines of the Oneworld alliance (联盟) have joined forces to give world travelers a simple way to plan and book a round-the-world journey. It's called the Oneworld Explorer program.
Oneworld Explorer is the perfect solution for a once-in-a-lifetime holiday or an extended business trip. It's a great way for you to explore the four corners of the earth in the safe hands of the eight Oneworld airlines.
You can have hundreds of destinations to choose from, because the Oneworld network covers the globe、And as you travel around the world, you'll have the support of 260,000 people from all our airlines, who are devoted to the success of our journey, helping you make smooth transfers and offering support all along the way.
The Oneworld goal is to make global travel easier and more rewarding for every one of our travelers、We try our best to make you feel at home, no matter how far from home your journey may take you.
We can offer travelers benefits on a scale beyond the reach of our individual(个人的)networks. You'll find more people and more information to guide you at every stage of your trip, making transfers smoother and global travel less of a challenge.
The Oneworld Explorer program is said to be most suitable for those who _____.

A.have been to the four comers of the earth B.travel around the world on business
C.want to explore the eight airlines D.need support all along the way

The advantage of the alliance lies in ________.

A.its detailed travel information B.its unique booking system
C.its longest business flights D.its global service network

We can learn from the last paragraph that Oneworld __________.

A.offers the lowest prices to its passengers
B.keeps passengers better informed of its operations
C.offers better services than any of its member airlines alone
D.is intended to make round-the-world trips more challenging

The purpose of the advertisement is to ___________.

A.promote a special flight program B.recommend a long business trip
C.describe an alliance flight D.introduce different airlines

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