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The fact that your hair turns grey becau...

    The fact that your hair turns grey because of stress is nothing more than an old wives' tale. It's true that stress isn't good for you, but it's not going to turn you into a silver fox just yet. In fact, the answer comes from the cells in your hair. These are what decide the color and, eventually, the fade to grey.

Most of us start to notice our first grey hairs by the time we hit our thirties. A general rule to go by is that by the age of 50, half of the population will have lost the color in 50 percent of their hair.

But why does it happen? Firstly, we need to understand how hair gets its color.

Your hair is made up of cells called melanocytes (黑色素细胞) which produce pigments (色素) as they grow into the hair fiber. There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.

As we age, the ability of the melanocytes to produce more pigments weakens. That's because our hair grows in different periods.

The growing period lasts between three and five years, after which our follicles (毛囊) turn off for about three months to rest and get ready to grow more hairs. This goes round and round and, after a time, our bodies aren't as good at producing new hairs.

Scientists are continuing to try and find ways to prevent greying hair. A team of scientists in France is working to try and stop the melanocytes from being damaged at the end of each hair cycle. They are trying to use a special enzyme () to protect the cells from damage. If successful, it could lead the way for new products that keep our hair full of color for years to come.

1.What does the phrase ''an old wives' tale'' in Paragraph 1 probably mean?

A.A wrong belief B.A useful talk

C.A scientific rule D.A helpful experience

2.What do we know about red hair?

A.It doesn’t turn grey as people get older.

B.It contains more pheomelanins than eumelanins.

C.The amount of pigments in it doesn't change over time.

D.People with red hair have weaker ability to produce pigments.

3.What do the French scientists aim to do?

A.To repair damaged hair follicles.

B.To protect hair cells against damage.

C.To shorten the hair cycle to protect the hair.

D.To study the relationship between health and hair color.

4.What can be a suitable title for the text?

A.Grey Hair: a Symbol of Huge Pressure.

B.Grey Hair: a Symbol of Declining Health.

C.Cells: the Cause of New Hair Growth.

D.Cells:the Cause of Color Change of Hair.

 

1.A 2.B 3.B 4.D 【解析】 这是一篇说明文。文章主要讲述了研究发现决定我们头发颜色的是头发里面的两种色素细胞:真黑色素和黑色素,前者生产黑色和棕色,后者产生红色和棕色。科学家们发现,只要保证色素细胞不受到损害,头发就不会变白。 1. 词义猜测题。根据第一段的The fact that your hair turns grey because of stress is nothing more than an old wives' tale. It's true that stress isn't good for you, but it's not going to turn you into a silver fox just yet.可知,你的头发是因为压力而变白的,这种说法只不过是an old wives' tale。压力对你没有好处这是对的,但也不会把你变成一头银发。根据句意推测划线部分的意思是“不正确的说法/无稽之谈”。A. A wrong belief(一个错误的信念)符合以上说法,故选A项。 2. 推理判断题。根据第四段的There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.(黑色素有两种不同的类型:真黑色素和黑色素。前者产生黑色和棕色色素,后者产生红色和黄色色素。这些色素的量决定了一个人是黑色、棕色、金色还是红色的头发)可推测,如果头发是红色,它含有的黑色素就比真黑色素多。B. It contains more pheomelanins than eumelanins.(比起真黑色素来它含有更多的黑色素)符合以上说法,故选B项。 3. 细节理解题。根据最后一段的A team of scientists in France is working to try and stop the melanocytes from being damaged at the end of each hair cycle. They are trying to use a special enzyme (酶) to protect the cells from damage.(法国的一个科学家团队正在努力阻止黑色素细胞在每次发丝周期结束时受损。他们试图用一种特殊的酶来保护细胞不受伤害)可知,法国科学家致力于保护头发细胞不受伤害。B. To protect hair cells against damage.(为了保护头发细胞不受伤害)符合以上说法,故选B项。 4. 主旨大意题。根据文章的主要内容,尤其是第四段的Your hair is made up of cells called melanocytes (黑色素细胞) which produce pigments (色素) as they grow into the hair fiber. There are two different types of melanins: eumelanins and pheomelanins. The former produces black and brown pigments, while the latter produces red and yellow pigments. The exact amount of these pigments decide whether a person has black, brown, blonde or red hair.(你的头发是由黑色素细胞构成的,在长成头发纤维的过程中它们可以生产色素。黑色素有两种不同的类型:真黑色素和黑色素。前者产生黑色和棕色色素,后者产生红色和黄色色素。这些色素的量决定了一个人是黑色、棕色、金色还是红色的头发)可知,本文主要讲述了决定我们头发颜色的是头发里面的黑色素细胞,如果能让它们不受到损害,我们的头发就不会变白。D. Cells:the Cause of Color Change of Hair.(细胞:头发改变颜色的原因)可以作为本文标题,故选D项。
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    Emilia Dobek traces her interest in space and the universe back to third grade when she and her father watched a blood moon — a total lunar eclipse (月食)---on the roof of their house.

Now a seven-grader at East Prairie Elementary School, Dobek recently won the national Discovery Education Beyond Challenge by designing a space station for traveling to Mars. She says that night watching the lunar eclipse launched a passion in her that has yet to run out of fuel.

So, when her teacher, Andrea Smeeton, received information about the national challenge, Smeeton said she immediately had one student in mind. “I knew she would love the challenge and that she would go way beyond in her research,” Smeeton said. “She immediately started researching bone density of astronauts and how to have sustenance on Mars.”

“My design will ensure the safety of the astronauts but also make sure their comfort is out of this world,” said Dobek. Dobck’s design calls for building the MSS or Mars Storage Station to accommodate the need for abundant supplies. She explains how her spacecraft—the Adventurer—will get into a space station before flying to the MSS to get supplies. Her design includes the SGF or SelfGrowing Farm, and she details how it would work with the elements on Mars.

Then there is physical and leisure activity for the astronauts under Dobck’s design. A. simulator (模拟器) allows astronauts to choose their exercise machine and virtual reality environment. Rooms have circular ceilings, she says, so astronauts will be able to watch downloaded shows and even see places on Earth, such as their homes. Chief among her immediate goals, she said, is to inspire with this project. want to tell other kids to follow their passions,” Dobek said. “Whatever they want to do, they should kind of just push for it. They should always try their best.”

1.What launched Dobek’s passion for space and the universe?

A.Winning the national challenge.

B.Observing the lunar eclipse with her father.

C.Studying with her teacher Andrea Smeeton.

D.Designing a space station for traveling to Mars.

2.How can astronauts entertain themselves in Dobek’s design?

A.By exercising in outer space. B.By playing virtual reality games.

C.By appreciating places on Earth. D.By enjoying shows of their homes.

3.What is Dobek’s major aim with her project?

A.To realize her immediate goals.

B.To create a leisure design for astronauts.

C.To get inspired by the national challenge.

D.To encourage others to pursue their interest.

4.What is the best title for this passage?

A.New Space Station Design

B.Leisure Activities for Astronauts

C.7th-grader Won National Prize

D.Patient Teacher Motivated Innovation.

 

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    Knowing what not to do at checkout and properly preparing for it can turn a potentially heated situation into a quick thank you and goodbye. Below we compiled a list of things you should remember at hotel checkout.

1. Don’t be late to checkout

Hotels may add an outrageously high price for being just a half-hour late. If you know you won’t make the cutoff time, it never hurts to call ahead and try to negotiate a potential charge.

2. Don’t forget to double check the room and safe

Make sure you don’t leave anything behind. If you have an early flight or checkout time, pack up as much as you can the night before so that last-minute rush isn’t too hurried. Also, be sure to take out anything in the room safe.

3. Don’t freak out

Spitting venom (毒液) at the assistant manager standing behind the front desk probably won’t help when dealing with an unexpected item on the bill. Being empathetic about how difficult it can be to deal with annoyed customers will likely go much further.

4. Don’t pay with cash or debit card (借记卡)

Disputing your bill after paying with cash is a lot harder than working with a credit card company to get a charge back. If you pay with a debit card, you may not have the protection to challenge a charge.

5. Don’t have the hotel call you a cab

If you want to save a few dollars, plan ahead and check if a ride-sharing service is going to be cheaper than a cab to the airport.

1.What may the hotel do if you are late for the checkout?

A.Negotiate a potential price.

B.Call ahead and cancel the reservation.

C.Charge extra money.

D.Give the room to other customers.

2.What should you do when the receptionist meets angry customers?

A.Spit at the assistant manager. B.Argue with the front desk.

C.Show understanding to the situation. D.Go much further away from it.

3.Why is it a good idea to use a ride-sharing service to get to the airport?

A.It helps the cab save dollars.

B.It reduces the burden of the hotel.

C.It is easy to get a charge back.

D.It costs the customers less money.

 

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注意:1.词数100左右;

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Dear David.

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Yours,

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增加:在缺词处加一个漏字符号(Λ),并在其下面写出该加的词。

删除:把多余的词用斜线()划掉。

修改:在错的词下划一横线,并在该词下面写出修改后的词。

注意:

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I'm writing to tell you about a shocked incident that happened in Beijing Zoo in the afternoon of Feb 23rd. I was visiting the zoo that afternoon while I heard bears roaring terribly. I hurried to the place where the bears lived at. I saw the black bear badly injured and one of them rolling on the ground painfully. It was hurt too serious to move a foot.

The people around are shocked, angry and blaming the wrongdoer. I learned that was a student from a famous university in Beijing who caused the trouble. He poured sulphuric acid(硫酸) onto the bears, or pretending to feed them.

What an shame! Animals are our friends and something must be done to prevent them from being injured.

Sincerely yours,

Li Hua

 

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China launched the Shenzhou manned spacecraft on Monday morning to transport two astronauts to the Tiangong space laboratory. The spacecraft 1.(send) skyward at 7:30 am atop a Long March 2F rocket from the Jiuquan Satellite Launch Center in Northwest China, 2.(carry) two male astronauts — Jing Haipeng and Chen Dong. After the launch, the spacecraft will travel two days before docking with the Tiangong , 3.was lifted from the Jiuquan center in mid-September. Then the astronauts will enter the space lab and stay there 4.30 days, and it will be the longest space stay by Chinese astronauts.

The core 5.(task) of the Shenzhou mission are to test rendezvous and docking technologies for the country’s 6.(plan) space station, to verify the life-support capability of the spacecraft-space lab combination as well as conduct 7.(science) research and test engineering experiments.

China is 8.third country in the world that has 9.(independent) fulfilled manned spaceflight following the former Soviet Union and the United States and 10.(it) space program aims to place a permanent manned space station, into service around 2022.

 

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