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 percent of Europeans. The other is found in 93 to 100 percent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.
Scientists have changed the color of a dark-striped zebra-fish（斑马鱼） to uniform gold by inserting a version of the pigment (色素) gene into a young fish. As with humans, zebra-fish skin color is determined by pigment cells, which contain melanin (黑色素). The number, size and darkness of melanin per pigment cell determine skin color.
It appears that, like the golden zebra-fish, light-skinned Europeans also have a mutation (变异) in the gene for melanin 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 zebra-fish 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 color, said Cheng.
The new discovery could lead to medical treatments for skin cancer. It also could lead to research into ways to change skin color without damaging it like chemical treatment did on Michael Jackson.The passage mainly tells us that ________.
| A．people can not change their skin color without any pain |
| 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．scientists have found out that people’s skin color is determined by the gene |
It can be inferred from the passage that _____________.
| A．nowadays people who want to change their skin color 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 color is determined by the pigment gene |
| C．find out the reason why the Africans’ skin color is dark |
| D．find out the ways of changing people’s skin color |
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 gene for melanin 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．unconcerned |
There is one language that is used in every country in the world. The people who use it are young and old, short and tall, thin and fat. It is everybody’s second language. It is easy to understand, although you can’t hear it. It is sign language.
When you wave to a friend who is across the street, you are using sign language. When you smile at someone, you are saying, “I w
ant to be friendly”, but you are not using speech. You are using sign language. When you raise your hand in class, you are saying, “Please ask me. I think I know the correct answer.”
Babies who can’t talk can point at things. They are using sign language. A policeman who wants to stop traffic holds up his hands. He is using sign language.
Many years ago, a French priest（神父）, Charles Michel de Epee, became interested in education for deaf people. He invented a finger alphabet (字母表). It is still in use. People can make the sign for letters and spell words with their hands, and deaf people can read and understand them. Soon there were schools for the deaf in many countries. The only university for the deaf is Gallaudet College in Washington, D.C.
Today, in the United States, there are special TV news programs for deaf people. The newsreader tells the news in sign language. At the same time, the words appear on the TV screen.
The actors in the Theatre of Deaf don’t spell every word. Sometimes they use hand signs. When they put two hands together, it means sandwich. They can make a roof with their hands when they want to show a house. One finger in front of an actor’s mouth can mean quiet. You can talk to people who are behind windows that are closed. And when you go swimming with your friends, you can have conversations und
er water.
How many hand signs do you use every day?. Which of the following about sign language is TRUE?
| A．It is a special language used in a few countries in the world. |
| B．It is a way to express one’s ideas without words. |
| C．It is only used by the deaf. |
| D．It can be heard. |
. If you want to express the idea that “I am very friendly” to someone, you will ______.
| A．raise your hand | B．put one hand onto the other |
| C．smile to the person | D．make a roof with your hands |
. Which of the following is TRUE according to the passage?
A. Hand signs instead of finger signs are used everyday.
B. There are schools, colleges and universities for the deaf in the USA.
C. The French priest Charles invented sign language.
D. Even babies are using sign language. .The passage is mainly about ______.
| A．an introduction to sign language | B．the importance of sign language |
| C．a famous priest in France | D．how to use sign language |
Mark Twain was a great writer. He was from the USA. He was born in 1835. He was also a famous speaker. He was famous for his sense of humour（幽默感）. Many people liked to listen to him talk because he liked to tell some interesting stories to make people laugh all the time.
One day Mark Twain was going to a small town because of his writing. Before he was going to leave, one of his friends said to him that there were always a lot of mosquitoes in the town and told him that he’d better not go there. Mark Twain waved (摇动) his hand and said, “It doesn’t matter. The mosquitoes are no relatives of mine. I don’t think they will come to visit me.”
After he arrived at the town, Mark Twain stayed in a small hotel near the station. He went into his room, but when he was just about to have a rest, quite a few（许多） mosquitoes flew about him. The waiters felt very sorry about that. “I’m very sorry, Mr. Mark Twain. There are too many mosquitoes in our town.” One of them said to him.
Mark Twain, however, made a joke, saying to the waiter, “The mosquitoes a
re very clever. They know my room number. They didn’t come into the wrong room.” What he said made all the people present laugh heartily.
But that night Mark Twain slept well. Do you know why? That was because all the waiters in the hotel were driving the mosquitoes away for him during the whole night. .That day Mark Twain went to the town _____.
| A．to see one of his friends |
| B．because he wanted to do something there for his writing |
| C．because he was told there were a lot of mosquitoes there |
| D．to see one of his relatives |
. The waiters felt sorry because _____.
| A．they did something wrong to Mark Twain |
| B．their hotel was too small |
| C．the room was not very clean |
| D．there were quite a few mosquitoes in Mark Twain’s room |
. All the people present laughed heartily because _____.
| A．the mosquitoes were very clever and they didn’t come into the wrong room |
| B．the mosquitoes knew Mark Twain’s room number |
| C．Mark Twain gave the waiters some nice presents |
| D．Mark Twain made a joke |
. From the story we know _____.
| A．no mosquitoes troubled Mark Twain in the night |
| B．the owner of the hotel told the waiters to look after Mark Twain well at night |
| C．Mark Twain didn’t have a good rest that night |
| D．there were not mosquitoes in the hotel any longer |
Hobbs was an orphan（孤儿）. He worked in a factory and every day he got a little money. Hard work made him thin and weak. He wanted to borrow a lot of money to learn to paint pictures, but he did not think he could pay off the debts.
One day a lawyer said to him, “One thousand dollars, and here is the money.” As Hobbs took the package of notes, he was very dumbfounded. He didn’t know where the money came from and how to spend it. He said to himself, “I could go to find a hotel and live like a rich man for a few days; or I give up my work in the factory and do what I’d like to do: painting pictures. I could do that for a few weeks, but what would I do after that? I should have lost my place in the factory and have no money
to live on. If it were a little less money, I would buy a new coat, or a radio, or give a dinner to my friends. If it were more, I could give up the work and pay for painting pictures. But it’s too much for one and too little for the other.”
“Here is the reading of your uncle’s will（遗嘱）,” said the lawyer, “telling what is to be done with this money after his death. I must ask you to remember one point. Your uncle has said you must bring me a paper showing exactly what you did with his money, as soon as you have spent it.”
“Yes, I see. I’ll do that,” said the young man... Hobbs wanted to borrow money to _______.
| A．study abroad | B．work abroad |
| C．pay off the debts | D．learn to paint pictures |
. What does the underlined word “dumbfounded” （in Paragraph 2） probably mean?
A．Surpri sed. |
B．Frightened. |
| C．Satisfied. | D．Excited. |
. With the money he got, at first Hobbs _______.
| A．planned to have a happy life for a few days |
| B．decided to give up his work in the factory |
| C．was to give a dinner to his friends |
| D．had no idea what to do |
.. Hobbs was asked to _______.
| A．tell the lawyer what he did with the money after spending it |
| B．read his uncle’s will |
| C．tell the lawyer what was to be done with the money |
| D．buy some pictures |
China’s second manned（人造的） space flight will be done by two astronauts（宇航员） over five days in 2005. “Shenzhou-VI will be sent into space sometime in 2005,” said Zuo Saichun, a spokesperson of the China Aerospace Science and Technology (CAST). “The spacecraf
t（宇宙飞船） will make new breakthroughs（突破性进展） in China’s manned space technology.”
Unlike Shenzhou-V, a little more than a year ago (in October, 2003), the next flight will see two astronauts fly in space for five days. Their capsule (太空舱) is designed to be capable（能够）of orbiting（绕轨道运行） for a whole week, the spokesperson said. “For the first time, astronauts will enter and live in the orbital module（舱） of the spacecraft to do scientific experiments,” said a statement from CAST. CAST did not say what those experiments will be.
In Shenzhou-VI, scientists have changed the spacecraft’s configuration (构形) to reduce its weight, and tried to improve the performance of on-board equipment. They have also worked to make sure of the energy supply of the spacecraft and further improve its safety. So far, scientists have worked out ways to solve problems on environmental control and life support. Shenzhou-VI will be sent into orbit atop（在……顶上） a Long March 2F rocket.
Meanwhile, a model of the Chang’e-1 satellite is expected to be sent to orbit the moon in two years. The satellite, part of the three-stage programme, would be followed by the landing of an unmanned vehicle on the moon in the second stage by 2010 and collecting samples（样品） of lunar soil by 2020 in the final stage, according to Sun Laiyan, director of the China National Space Administration. . Which of the following about Shenzhou-VI is NOT true?
A．It will be sent into space in 2005. |
B．It is capable of orbiting for two weeks. |
C．It will be sent into orbit atop a Long March 2F rocket. |
D．It will be sent into space with two astronauts. |
. According to the passage, the following problems should be solved before Shenzhou-VI is sent into space EXCEPT ______.
| A．environmental control | B．energy supply |
C．life support | D．lunar soil collecting |
. Which of the following does NOT belong to the three-stage programme?
| A．Shenzhou-VI’s being sent into space. |
B．A model of the Chang’e-1 satellite will be sent to orbit the moon. |
C．The landing of an unmanned vehicle on the moon. |
D．Collecting samples of lunar soil.  |
. The passage mainly tells us ______.
| A．some problems need solving before Shenzhou-VI is sent into space |
B．Shenzhou-VI will be sent into space in 2005 |
C．what China’s space programme is |
D．how China’s three-stage programme is carried out |
February has long been a month of romance. With the sweet smell of roses in the air, romantic films hit cinemas and love stories fill newspapers and magazines.
On the 14th day, it is a custom for a boy to take his girlfriend out to dinner, buy her flowers and chocolates, write poems, sing to her or even spell out her name with rose petals(花瓣)! This is what you see on Valentine’s Day, a day named after Valentine who was a priest（神父） in the third century Rome. When the emperor (皇帝) decided that single men could become better soldiers than those with wives, he didn’t allow marriage.
But Valentine continued to perform marriage ceremonies（仪式） for young lovers in secret. When his actions were discovered, the emperor sentenced him to death. While in prison, it is said that Valentine fell in love with the daughter of his prison guard. Before his death, he wrote her a letter, which he signed “From your Valentine”, an expression that is still in use today. Valentine died for what he believed in and so he was made a Saint (圣徒), as well as becoming one of history’s most romantic characters.
Nowadays, Valentine’s Day is also popular among Chinese young people. Some students are planning to make Valentine’s cards for parents, teachers and friends. Others want to hold parties at which they will exchange small gifts and eat heart-shaped cakes. The idea is to have fun and encourage people to share in the spirit of St. Valentine... Why did the emperor in Rome not allow marriage in his country?
| A．Because there were few women in his country at that time. |
B．Because he thought men without wives could be better soldiers. |
| C．Because there wasn’t enough food for so many people. |
| D．Because he wanted to control the birth rate. |
.. Valentine was put into prison because ______.
| A．he killed one of the soldiers |
| B．he stole a lot of food |
| C．he didn’t obey the emperor’s order |
| D．he didn’t want to be a soldier |
. The last paragraph mainly tells us ______.
| A．students in China send cards to their teachers |
| B．it is a good idea to celebrate Valentine’s Day in China |
| C．it is interesting to celebrate Valentine’s Day in China |
| D．Valentine’s Day is also popular in China now |
.The best title for this passage should be ______.
| A．Valentine’s Day | B．A Brave Priest |
| C．Valentine’s Day in China | D．A Romantic Man |
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