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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 of the sun(太阳光紫外线), 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.
The passage mainly tells us that ________.

A.people can not change their skin colour without any pain
B.the new discovery could lead to search into 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 people who want to change their skin colour have to suffer a lot from the damage caused by the chemical treatment B.Europeans and Africans have the same gene
C.the new discovery could help to find medical treatments for skin cancer D.there are two kinds of 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 peopl’s skin colour

The reason why Europeans are light-skinned is probably that ________.

A.they are born light-skinned people
B.light-skinned Europeans have mutation in the gen for melanosome production
C.they have fewer activities outside D.they pay much attention to protecting their skin

The writer’s attitude towards the discovery is ________.

A.neutral B.negative C.positive D.indifferent
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Acorn Bank Garden & water mill
A delightful walled garden with old varieties of fruit trees and flower borders, set against the backdrop of a 17th-century red sandstone house overlooking the Eden Valley. Herb garden planted with over 200 medicinal and culinary herbs. Dogs on leads are welcome on woodland walks. Children’s activity sheet available.
Temple Soverby, Near Penrich, CA 10 lsp Tel: 017683 61893
Open:
19 March—30 October, daily except Monday and Tuesday, 10 am—5pm
Tearoom open from 11am—4. 30 pm, Shop 10am—5pm
Price: Adult £3, Child £1.5, Family £7.5
The Beatrix Potter Gallery
Original sketches and watercolors by Beatrix Potter for her children’s tales. 2005 exhibition will feature. The Tale of Mrs Tiggy-Winkle and The Tale of the Pie and The Patty-Pan. Also on display in this atmospheric 17t h-century building is information on Beatrix Potter’s life.
Beatrix Potter Gallery, Hawkshead, LA22 ONS Tel: 015394 36355
Open:
19 March—30 October, 10am—4. 30 pm, daily except Thursday and Friday. Also open 12—20 February, 2 & 3 June and 27 & 28 October.
Price: Adult £3.50, Child £1.70, Family £8.70
Hill Top
Beatrix Potter wrote and illustrated many of the famous children’s stories in this 17th-century farmhouse which she bought 100 years ago. Today you can view her personal treasures and step into the garden which is planted with flowers and vegetables, just as it would have been in Beatrix Potter’s time.
Please note that this is a small and popular house, which gets very busy especially in school holidays. At peak times there are queues and by the end of the day not all visitors may be able to visit the house (we apologize for this). Please collect a timed ticket (including NT members) from the ticket office in the car park on your arrival.
Hill Top, Near Sawrey, La22 OLF Tel: 015394 36269
Open:
19 March—30 October, 10: 30 am—4. 30 pm, daily except Thursday and Friday. Also open Thursday in August and 2 & 3 June and 27 & 28 October.
Shop and Garden open Thursday and Friday, 10:am—5 pm. Ring for winter opening.
Price: Adult £5, Child £2, Family £12

. From the ads mentioned above, we can learn _______.

A.visitors can admire the scene of the Beatrix Potter’s time in Hill Top
B.visitors can admire the beautiful natural in both the Beatrix Gallery and Hill Top
C.the Beatrix Potter Gallery is more popular with children than Hill Top
D.Beatrix Gallery neighbors Hill Top

If the Smiths and their 2 children visit the 3 sites, they will have to pay _______.

A.£28.2 B.£23.4 C.£28 D.£33

If you have the tickets, you must be able to _______.

A.visit Hill Top at opening time
B.visit the Beatrix Potter Gallery on Friday
C.visit Acorn Bank at opening time
D.visit the three sites at any time

We can learn from the ads that _______.

A.you can enjoy yourself with a dog as you like at Acorn Bank
B.it is convenient for you to get a timed ticket for Hill Top
C.children who have passed a quiz will be admitted to the Beatrix Potter Gallery
D.you can book the tickets for Hill Top through the telephone number 015394 36355

When a group of children politely stop a conversation with you, saying: “We have to go to work now,” you’re left feeling surprised and certainly uneasy. After all, this is the 1990s and the idea of children working is just unthinkable. That is, until you are told that they are all pupils of stage schools, and that the “work” they go off to is to go on the stage in a theatre.
  Stage schools often act as agencies(代理机构)to supply children for stage and television work. More worthy of the name “stage school” are those few places where children attend full time, with a training for the theatre and a general education.
  A visit to such schools will leave you in no doubt that the children enjoy themselves. After all, what lively children wouldn’t settle for spending only half the day doing ordinary school work, and acting, singing or dancing their way through the other half of the day?
 Then of course there are times for the children to make a name and make a little money in some big shows. Some stage schools give their children too much professional work at such a young age. But the law is very tight on the amount they can do. Those under 13 are limited to 40 days in the year; those over 13 to 80 days.
 The schools themselves admit that not all children will be successful in the profession for which they are being trained. So what happens to those who don’t make it? While all the leading schools say they place great importance on children getting good study results, the facts seem to suggest this is not always the case.
 People would stop feeling uneasy when realizing that the children they’re talking to________.
  

A.attend a stage school     B.are going to the theatre
  
C.have got some work to do    D.love singing and dancing

   In the writer’s opinion, a good stage school should ________.
  

A.produce star performers
  
B.help pupils improve their study skills
  
C.train pupils in language and performing arts
  
D.provide a general education and stage training.

 “Professional work” as used in the text means ________.
  

A.ordinary school work      B.money-making performances
  
C.stage training at school    D.acting, singing or dancing after class

  Which of the following best describes how the writer feels about stage schools?
  

A.He thinks highly of what they have to offer.    
  
B.He favours an early start in the training of performing arts.
  
C.He feels uncomfortable about children putting on night shows.
  
D.He doubts the standard of ordinary education they have reached.

Maybe ten-year-old Elizabeth put it best when she said to her father, "But, Dad, you can't be healthy if you're dead."
  Dad, in a hurry to get home before dark so he could go for a run, had forgotten to wear his safety belt-- a mistake 75% of US population make every day. The big question is why.
 There have been many myths about safety belt ever since their first appearance in cars some forty years ago. The following are three of the most common.
 Myth the Number One: It's best to be "thrown clear" of a serious accident.
  Truth: Sorry, but any accident serious enough to "throw you clear" is able going to be serious enough to give you a very bad landing. And chances are you'll have traveled through a windshield (挡风玻璃)or door to do it. Studies show that chances of dying after a car accident are twenty-five times in cases where people are "thrown clear".
 Myth Number Two: Safety-bets "trap" people in cars that are burning or sinking in water.
Truth: Sorry again, but studies show that people knocked unconscious (昏迷) due to not wearing safety belts have a greater chance of dying in these accidents. People wearing safety belts are usually protected to the point of having in these accidents. People wearing safety belts are usually protected to the point of having a clear head to free themselves from such dangerous situation, not to be trapped in them.
 Myth Number Three: Safety belts aren't needed at speeds of less than 30 miles per hour (mph).
 Truth: When two cars traveling at 30 mph hit each other, an unbelted driver would meet the windshield with a force equal to diving headfirst into the ground from a height of 10 metres.
Why did Elizabeth say to her father, "But, Dad, you can't be healthy if you're dead"?

A.He was driving at great speed.
B.He was running across the street.
C.He didn't have his safety belt on.
D.He didn't take his medicine on time.

The reason father was in a hurry to get home was that he __________.

A.wasn't feeling very well B.hated to drive in the dark
C.wanted to take some exercise D.didn't want to be caught by the people

According to the text, to be "thrown clear" of a serious accident is very dangerous because you ________.

A.may be knocked down by other cars.
B.may get serious hurt thrown out of the car
C.may find it impossible to get away from the seat
D.may get caught in the car door

Some people prefer to drive without wearing a safety belt because they believe _______.

A.the belt prevents them from escaping in an accident
B.they will be unable to think clearly in an accident
C.they will be caught when help comes
D.cars catch fire easily

What is the advice given in the test?

A.Never drive faster than 30 miles an hour.
B.Try your best to save yourself in a car accident.
C.Never forget to wear the safety belt while driving.
D.Drive slowly while you're not wearing a safety belt.

For thousands of years, man has enjoyed the taste of apples. Apples, which are about 85 percent water, grow almost everywhere in the world but the hottest and coldest areas (地区). Among the leading countries in apple production are China, France and the United States.
There are various kinds of apples, but a very few make up the majority of those grown for sale. The three most common kinds grown in the United States are Delicious, golden Delicious, and McIntosh.
 Apples are different in colour, size, and taste. The colour of the skin may be red, green, or yellow. They have various sizes, with Delicious apples being among the largest. The taste may be sweet or tart (酸的). Generally, sweet apples are eaten fresh while tart apples are used to make applesauce (苹果酱).
 Apple trees may grow as tall as twelve metres. They do best in areas that have very cold winters. Although no fruit is yielded during the winter, this cold period is good for the tree.
It can be learned from the text that Delicious apples are _______________

A.grown in France. B.sold everywhere.
C.very big.       D.quite sweet.

Cold winter weather is good for _______________

A.the growth of apple trees.
B.producing large apples.
C.improving the taste of apples.
D.the increase of water in apples.

China, France and the United States are considered to _______________

A.be large producers of apples.
B.be large producers of applesauce.
C.have the longest history in apple production.
D.have the coldest winter among apple producing countries.

The word yielded in the last sentence means _______________

A.improved. B.increased.
C.produced.  D.sold.

Today, roller skating is easy and fun. But a long time ago, it wasn't easy at all. Before 1750, the idea of skating didn't exist. That changed because of a man named Joseph Merlin. Merlin's work was making musical instruments. In his spare time he liked to play the violin. Joseph Merlin was a man of ideas and dreams. People called him a dreamer.
 One day Merlin received an invitation to attend a fancy dress ball. He was very pleased and a little excited. As the day of the party came near, Merlin began to think how to make a grand entrance at the party. He had an idea. He thought he would get a lot of attention if he could skate into the room.
  Merlin tried different ways to make himself roll. Finally, he decided to put two wheels under each shoe. These were the first roller skates. Merlin was very proud of his invention and dreamed of arriving at the party on wheels while playing the violin.
 On the night of the party Merlin rolled into the room playing his violin. Everyone was astonished to see him. There was just one problem. Merlin had no way to stop his roller skates. He rolled on and on. Suddenly, he ran into a huge mirror that was hanging on the wall. Down fell the mirror, breaking to pieces. Nobody forgot Merlin's grand entrance for a long time!
The text is mainly about_________.
 

A.a strange man
 
B.an unusual party
 
C.how roller skating began
 
D.how people enjoyed themselves in the 18th century

 People thought Merlin was a dreamer because he________.
 

A.often gave others surprises     B.was a gifted musician
 
C.invented the roller skates     D.was full of imagination

  Merlin put wheels under his shoes in order to_______.
 

A.impress the party guests      B.arrive at the party sooner
 
C.test his invention         D.show his skill in walking on wheels

  What is the main point the writer is trying to make in the last paragraph?
 

A.The roller skates needed further improvement.
 
B.The party guests took Merlin for a fool.
 
C.Merlin succeeded beyond expectation.
 
D.Merlin got himself into trouble.

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