Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes.Scientists have found the gene that determines skin color.
The gene comes in two versions, one of which is found in 99 per cent of Europeans.The other is found in 93 t0 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark - striped zebrafish(斑马鱼) to uniform gold by inserting a version of the pigment(色素) gene into a young fish.As with humans, zebrafish skin color is deter-mined by pigment cells，which contain melanin(黑色素).The number, size and darkness of melanin perpigment cell determine skin color.
It appears that, like the golden zebrafish, light - skinned Europeans also have a mutation (变异) in the gene for melanin production.This results in less pigrnented skin.
However, Keith Cheng, leader of the research team, points out that the mutation is different in hu-man ancl zebrafish genes.
Humans acquired dark skin in Africa about l.5 million years ago to protect bodies from ultra - violetrays of the sun. which can cause skin cancer.
But when modem humans leave Africa to live in northem 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 color, said Cheng.
The new discovery could lead to medical treatments for skin cancer.lt also could lead to research in-to ways to change skin color without damaging it like chemical treatment did on Michael Jackson.Scientists have done an experiment on a dark -striped zebrafish in order to
| A．fincl the different genes o humans' |
| B．prove the humans' skin color is determined by the pigment gene |
| C．find out the reason why the Africans' skin color is dark |
| D．fincl out the ways of changing people's skin color |
lt can be inferred from the passage that .
| A．nowadays people who want to change their skin color have to suffer 8 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 |
The passage mainly tells us that .
| A．scientists have found out that people's skin color is determined by the gene |
| B．the new discovery could lead to research into ways to change skin color safely |
| C．pop king Michael Jackson often changed his skin color as he liked |
| D．people can not change their skin color without any pain |
The reason why Europeans are light - skinned is probably that .
| A．they are bom light - skinned people |
| B．light - skinned Europeans have mutation in the gene for melanin production |
| C．they have fewer activities outside |
| D．they pay much attention to protecting their skin |
The writer's attitude towarcls the discovery is .
| A．neutral | B．negative | C．indifferent | D．positive |
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Do dogs understand us?
Be careful what you say around your dog. It might understand more than you think.
A border collie named Rico recognizes the names of about 200 objects, say researchers in Germany. The dog also appears to be able to learn new words as easily as a 3-year-old child. Its word-learning skills are as good as those of a parrot or chimpanzee(黑猩猩).
In one experiment, the researchers took all 200 items that Rico is supposed to know and divided the into 20groups of 10 objects. Then the owner told the dog to go and fetch one of the items and bring it back. In four tests,Rico got 37 out of 40 commands right. As the dog couldn't see anyone to get clues, the scientists believe Rico must understand the meanings of certain words.
In another experiment, the scientists took one toy that Rico had never seen before and put it in a room
with seven toys whose names the dog already knew. The owner then told Rico to fetch the object, using a word the dog had never heard before.
The correct object was chosen in seven out of l0 tests, suggesting that the dog had worked out the answer by process of elimination(排除法). A month later, Rico remembered half of the new names, which is even more impressive.
Rico is thought to be smarter than the average dog. For one thing, Rico is a border collie, a breed (种)known for its mental abilities. In addition, the 9-year-old dog has been trained to fetch toys by their names since the age of nine months.
It's hard to know if all dogs understand at least some of the words we say. Even if they do, they can't talk back. Still, it wouldn't hurt to sweet-talk your dog every now and then. You might just get a big, wet kiss in return!
60. From paragraph 2 we know that ______________.
A. animals are as clever as human beings
B. dogs are smarter than parrots and chimpanzees
C. chimpanzees have very good word-learning skills
D. dogs have 
similar 'learning abilities as 3-year-old children
61. Both experiments show that__________
A. Rico is smart enough to get all commands right
B. Rico can recognize different things including toys
C. Rico has developed the ability of learning mathematics
D. Rico won't forget the names of objects once recognizing them
62. Which of the following statements is true?
A. The purpose of the experiments is to show the border collie's mental abilities.
B. Rico has a better memory partly because of its proper early training.
C. The border collie is world-famous for recognizing objects.
D. Rico is born to understand its owner's commands.
63. What does the writer want to tell us?
A. To train your dog. B. To talk to your dog.
C. To be friendly to your dog. D. To be careful with your dog.
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III. Reading comprehension30%:
WASHINGTON---Worldwide sales of personal computer in 1995 rose 24.7 percent over 1994 with Compaq（美国康柏电脑公司）holding its first—place position while IBM overcame（击败）Apple for the No.2 slot （表上排名）,according to Dataquest.
A total of 59.7 million computers were sold around the world with important gains（获得）in Japan and Europe.
Compaq sold 5.99 million computers ,or 10percent of the market ,unchanged from 1994.
IBM sold 4.7 m
illion with an 8 percent share of the market compared with 8.2 percent in 1994 .
Apple sold 4.7 million ,or 7.8 percent of the trade ,compared with 8.4 percent in 1994.
Their lost market share was taken up by Packard Bell and NEC ,which sold 3.1 million and 2.8 million computers separately.
56．Which company was the first in selling computers in 1994?
A．Compaq B．IBM C．Apple D．NEC
57．Which company sold the third most computers in 1995?
A．Compaq B．IBM C．Apple D．NEC
58．What was the market share of Compaq in 1994?
A．5.99% B．8.2% C．8.4% D．10%
59．Packard Bell and NEC take up about____________ of the market share in 1995.
A．8.2% B．52% C．10% D．5%
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I travel a lot, and I find out different “styles” of directions every time I ask “How can I get to the post office?”
Foreign tourists are often confused(困惑) in Japan because most streets there don’t have names; in Japan, people use landmarks(地标) in their directions instead of street names. For example, the Japanese will say to travelers, “Go straight down to the corner. Turn left at the big hotel and go past a fruit market. The post office is across from the bus stop.”
In the countryside of the American Midwest, there are not usually many landmarks. There are no mountains, so the land is very flat; in many places there are no towns or buildings within miles. Instead of landmarks, people will tell you directions and distances. In Kansas or Iowa, for example, people will say, “Go north two miles. Turn east, and then go another mile.”
People in Los Angeles, California, have no idea of distance on the map; they measure distance in time, not miles. “How far away is the post office?” you ask. “Oh,” they answer, “it’s about five minutes from here.” You say, “Yes, but how many miles away is it?” They don’t know.
It’s true that a person doesn’t know the answer to your question sometimes. What happens in such a situation? A New Yorker might say, “Sorry, I have no idea.” But in Yucatan, Mexico, no one answers “I don’t know.” People in Yucatan believe that “I don’t know” is impolite. They usually give an answer, often a wrong one. A tourist can get very, very lost in Yucatan!
67. When a tourist asks the Japanese the way to a certain place, they usually ______.
A. describe the place carefully B. show him a map of the place
C. tell him the names of the streets D. refer to recognizable buildings and places
68. What is the place where people measure distance in time?
A. New York.. B. Los Angeles. C. Kansas. D. Iowa.
69. People in Yucatan may give a tourist a wrong answer ______.
A. in order to save time B. because of honesty
C. so as to be polite D. for fun
70. What can we infer from the text?
A. It’s important for travelers to understand cultural differences.
B. It’s useful for travelers to know how to ask the way properly.
C. People have similar understandings of politeness.
D. New Yorkers are generally friendly to visitors.
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What is “Walk to School”?
Now we are working on a programme of “Walk to School”. We would like as many parents and children as possible to take part, even if in a small way. Children who walk to and from school along with their parents can learn essential (基本的) road safety and life skills.
You can take part by…
Walking to and from school with your child every day.
■ Walking for one or two days during the week.
■ Encouraging others to walk, if you already do.
Walking is great!
■ Walking is great exercise！A walk is good for your body and can keep you fit.
■ You won’t have to waste time looking for a parking site.
■ It’s free. You’ll save money by not using the car.
■ It’s pollution free.
■ It’s a good chance to talk to your children and to meet other parents, too.
Enjoying walking to school!
Here are some suggestions to help you and your child enjoy walking to school.
■ Plan a safe route together.
■ Teach children what a kerb (马路牙子) is and what it means.
■ Encourage your child to help you choose the safest places to cross the road.
■ Look at and discuss the things you see on your way － especially road signs and what they mean.
Walk to school! Thousands of parents and children already take part, could you?
Please go to www.walktoschool.org.uk for more information.
63. Who are encouraged to take part in the programme of “Walk to School”?
A. Children. B. Parents and children.
C. Bus drivers. D. Teachers.
64. By walking to and from school, children can learn ________.
A. driving skills B. road safety and life skills
C. running skills D. knowledge about science
65. What is the first thing to do if you want to enjoy your walking to school?
A. Plan a safe route with your children.
B. Learn what a kerb is and its meaning.
C. Choose the safest places to cross the road.
D. Find road signs and know their meanings.
66. According to the writer, you can learn more about “Walk to School” by________.
A. reading a newspaper B. making a phone call
C. going to the Internet D. having a traffic lesson
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There’re five people at our table, including myself. I’ve already learnt a great deal about them in the short time we’ve been at sea, although we rarely meet except at meal times.
First of all, there’s Dr Stone. He’s a man of about sixty five, with gray hair and a friendly face. He gave up his work a short while ago and is now traveling round the world before he retires to some quiet country village. As a young man, he served for many years as a doctor in the Army and visited many countries. He’s told us a lot about the city to which we are going.
Then there’s “Grandmother”. I call her that because her name escapes me. In spite of being a grandmother, she looks rather young, not more than fifty, She’s on her way to visit a daughter who went to Australia some years ago. Naturally she is very excited at the thought of seeing her again, and her three grandchildren, whom she has never seen.
Then there’s a man I don’t care for very much, an engineer by the name of Barlow. He has been on leave in England and is now returning to his work in Singapore.
The other person who sits at our table is Mrs. Hunt. I’ve found out hardly anything about her. She’s extremely quiet and rarely talks, except to consult(咨询)the doctor about children’s various illness. She’s on her way to join her husband in India.
60. What can we know about Mr. Stone?
A. He is a doctor in the Army now.
B. He is going to give up his work.
C. He knows a lot about the city the author is going to.
D. He has been retired for many years.
61. The writer calls the second person “Grandmother” because_______.
A. she looks old B. She has three daughters
C. he respects her D. he can’t think of her name
62. Which of the following is TRUE?
A. Dr Stone lives in a quiet village now. B. “Grandmother” is an Australian.
C. Barlow works in Singapore D. Mrs Hunt is a woman of many words.