If your head is overheating, you are very likely to yawn soon, according to a new study that has found the main purpose of yawning is to control brain temperature. The study explains several mysteries 题目和参考答案——青夏教育精英家教网—

题目内容

If your head is overheating, you are very likely to yawn(打哈欠) soon, according to a new study that has found the main purpose of yawning is to control brain temperature. The study explains several mysteries about yawning, such as why it’s most commonly done just before and after sleeping, why certain diseases lead to too much yawning, and why breathing though the nose often stops yawning.

“Brains are like computers,” Andrew Gallup, a researcher in the department of Biology at Binghamton University who led the study, said. “They operate best when cool.”

He and his co-workers Micheal Miller and Anne Clark did researches on yawning in parakeets(长尾小鹦鹉) , which have relatively large brains, live wild in Australia, often experience temperature changes, and, most importantly, do not yawn when others yawn, as humans and some other animals do.

For the study, the scientists put parakeets under three different conditions: increasing temperature, high temperature and normal temperature. While the frequency(频率) of yawns did not increase under the latter two conditions, it increased greatly when the researchers increased the temperature.

It’s now believed yawning operates like a radiator(散热器).

If air in the atmosphere is cooler than the brain and body temperatures, taking it in quickly cools blood, which in turn cools the brain. The new findings also explain why tired people often yawn. Both tiredness and sleep loss can increase brain temperature, while yawning can cool down the brain.

In the future, researchers may focus more on brain temperature and its role in diseases and their symptoms. But the new study on yawning changes the popular idea that yawns are just signs of getting tired of something.

49. What’s the best title for the passage?

A. Why don’t people yawn at normal temperature?

B. The yawn explained—it cools your brain.

C. Yawning operates like a radiator.

D. The cause of yawning—finally found out.

50. The main reason why researchers chose parakeets to do the research is that parakeets______.

A. have very large brains

B. live wild in Australia

C. are not affected by others’ yawning

D. experience frequent temperature changes

51. The writer may suggest doing all of the following to stop yawning EXCEPT______.

A. breathing through the nose

B. turning up the heat

C. enjoying some cool wind

D. putting a cold towel on your forehead

52. In which section of a newspaper would you most probably read this passage?

A. Discovery. B. Education. C. Health. D. Mystery.

49---52 BCBA

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完形填空 (共20 小题；每小题1分；满分20分)

阅读下面短文, 掌握其大意, 然后从 1---20各题所给的四个选项中,选出最佳选项.

Seven loyal readers came to the Teens' office two weeks ago. They had a wonderful day learning how to make a newspaper. But what 1 made them excited was that they had their say(发言权).

"What most 2 me was when I was saying something, I found all eyes were on me," said Tang Shining, one of the students. Her friend, Li Chunbei 3 , and felt very glad that when she was talking, the editors nodded and 4 took notes.

Students are happy to see the editors listen to their 5 . You may often 6 about being neglected（忽视） by teachers and parents. 7 before complaining please make sure that you have already spoken about your 8 .

Traditionally in China, teachers at school and parents were 9 the ones to tell teenagers what they should and shouldn't do. The young are 10 to doing what they are told, rather than thinking by themselves. But then their ideas would be locked in their brain and not be 11 .

A girl wrote to Teens about her family story. She 12 to be very sad because her father seldom talked and played with her. After years of consideration, she 13 decided to write her father a letter, telling him about her sadness. To her 14 , the father 15 , saying that he didn't realize his mistake. From then on, he really 16 .

Sometimes, we need to let our 17 be heard, so others can understand our thoughts and feelings.

Don' t be afraid of being 18 for what you have done. You know it is your 19 to speak your mind. Even if your suggestions are denied, at least you have tried your best. You will not be left with any 20 .

1.A. really B. directly C. completely D. immediately

2.A. disappointed B. impressed C. frightened D. horrified

3.A. refused B. disagreed C. agreed D. disliked

4.A. still B. yet C. already D. even

5.A. opinions B. speeches C. songs C. articles

6.A. talk B. complain C. write D. speak

7.A. And B. So C. But D. Instead

8.A. pleasure B. love C. hatred D. worry

9.A. seldom B. never C. always D. sometimes

10.A. used B. reduced C. devoted D. told

11.A. remembered B. reused C. touched D. heard

12.A. used B. pretended C. seemed D. had

13.A. sadly B. suddenly C. angrily D. finally

14.A. sorrow B. disappointment C. surprise D. satisfaction

15.A. apologized B. smiled C. laughed D. sighed

16.A. exchanged B. changed C. left D. played

17.A. voices B. decisions C. suggestions D. secrets

18.A. published B. blamed C. beaten D. fined

19.A. duty B. task C. right D. pleasure

20.A. regret B. sadness C. trouble D. difficulty

EBay will launch an online group gift-buying service today designed to make it easier for several people to chip in, buy and pay for gifts using their social-network and e-mail contacts．

EBay North America Vice President Christopher Payne says it is going to be a major step forward in social commerce, which is the still-small practice of selling products through social networks．Online retail experts aren't as certain, but eBay says the new tool makes it easier for friends and relatives to chip in （凑钱） for gifts because it eliminates the headache of collecting contributions．It can also be used for family members to pitch in to buy, say, an expensive child seat for a mother．

Anything on eBay that's available immediately, rather than up for bid, can be purchased this way starting today at groupgifts．eBay．com．If members of an extended family wanted to buy a gift for one member, one person would choose a gift — or have one recommended by eBay — and invite family members to chip in using Facebook or e-mail．Those who wanted to join in would choose an amount to contribute （or agree to pay a requested amount） and pay using either PayPal or a credit card．They could also add a personal note．

If enough people don't chip in, the organizer can ask people to contribute more or choose a less expensive gift．

"I see myself using this most in cases when I typically might not buy someone what they want because of price," says Nitzan Shaer of Boston, who was part of an online test of the site．

EBay, with its 200 million products, millions of sellers and mobile commerce proficiency, is a logical place to pull together the products, groups of buyers and payment tools, Payne says．

At least 12 sites, such as FrumUs．com and eDivvy．com, facilitate （便于,利于） group purchases but don't sell products．Although a handful of retailers, including Victoria's Secret and 1-800-Flowers, sell products through Facebook, Payne says he expects social commerce will take off as rapidly as shopping using mobile devices．EBay did more than $600 million in sales on mobile devices last year and expects mobile sales to increase to $1．5 billion this year．

Although one in five consumers surveyed said they'd used Facebook for shopping in the past year, 88% said they would not be buying holiday gifts through a social network, mobile phone or smartphone．Of these, 26% were reluctant because of security or privacy concerns, and 20% were unclear about the benefits of using phones or Facebook to shop．

1.What procedure should be followed if your extended family intends to buy your grandpa an 80^th birthday gift?

①Asking family members to contribute more money if enough members don’t chip in

②Choosing a gift at groupgifts．eBay．com

③Paying using PayPal or a credit card

④Contributing or agreeing to pay a requested amount of money via Facebook or e-mail

A．②-①-③-④	B．①-③-②-④
C．②-④-①-③	D．②-③-④-①

2.Where can we most probably read this text?

A．In a research paper	B．In a travel magazine
C．In a microblog	D．On a website

3.What does “it” mean in the 2^nd paragraph?

A．The online group gift-buying service

B．People’s social-network and e-mail contacts

C．A major step forward in social commerce

D．The still-small practice of selling products through social networks

4.It can be inferred from the text that ______．

A．through eBay’s new tool, 200 million products on eBay are available to online shoppers

B．social commerce can eliminate the headache of collecting contributions

C．eBay’s new tool will gain mass adoption by online shoppers

D．with the help of eBay’s new tool, FrumUs．com and eDivvy．com will also sell products

Allan goes everywhere with Birgitta Anderson, a 54-year-old secretary. He moves around her office at work and goes shopping with her. ‘Most people don't seem to mind Allan,’ says Birgitta, who thinks he is wonderful. 'He's my fourth child,' she says. She may think of him and treat him that way, buying his food, paying his health bills and his taxes, but in fact Allan is a dog. Birgitta and Allan live in Sweden, a country where everyone is expected to lead an orderly life according to rules laid down by the government, which also provides （提供）a high level of care for its people. This level of care costs money. People in Sweden pay taxes on everything, so aren't surprised to find that owning a dog means yet more taxes. Some people are paying as much as 500 Swedish kronor in taxes a year for the right to keep their dog, money that is spent by the government on dog hospitals and sometimes medical treatment for a dog that falls ill. However, most such treatment is expensive, so owners often decide to pay health and even life insurance （保险）for their dog. In Sweden dog owners must pay for any damage （损坏）their dog does. A Swedish Kennel Club official explains what this means: if your dog runs out on the road and gets hit by a passing car you, as the owner, have to pay for any damage done to the car, even if your dog has been killed in the accident.

1. Birgitta pays taxes for Allan because .

A. he is her dog B. he is her child C. he follows her everywhere D. he often falls ill

2.The money paid as dog taxes is used to .

A. keep a high level of care for the people B. pay for damage done by dogs

C. provide medical care for dogs D. buy insurance for dog owners

3. If a dog causes a car accident and gets killed, who should pay for the damage done to the car?

A. The owner of the car. B. The owner of the dog.

C. The insurance company（公司）. D. The government.

4.From the text it can be inferred that in Sweden .

A. dogs are welcome in public places B. keeping dogs means asking for trouble

C. many car accidents are caused by dogs D. people care much about dogs

No one wants to look stupid or do the wrong thing at a new job. It is important to make the right impression from the very first day. You will face new people. You will be in a new place.

It may be difficult to know what to do. Here are five tips to help you make it through the first days at a new job:

1. First impressions can last forever. Make sure you make a good one. Before your first day, find out if your new job has a dress code (rules about what you can wear to work). If so, be sure to follow it. No matter what, always be neat and clean.

2. Get to work on time. Give yourself an extra15 minutes to make sure you arrive on time.

3. Pay attention to introductions. One of the first things that your supervisor may do is to introduce you to co-workers. These co-workers will be important to you. They are the ones who will answer your questions when the boss is not around.

4. Ask plenty of questions. Make sure that your supervisor has told you what is expected of you. If he or she has not told you your duties, ask for a list. Set daily and weekly goals for yourself.

5. Never be the first one to leave. Observe(观察) what your co-workers do around quitting time (下班时间). It does not look good for you to be eager to leave.

1. Before you arrive at work on the first day, you should __________.

A. dress in a right way B. introduce yourself

C. know your duties D. know your co-workers well

2.According to the passage, which of the following statements is TRUE?

A. You should be the first one to arrive at work.

B. You should ask your co-workers about your duties.

C. You should not be eager to go back home after work.

D. You are required to arrive 15 minutes earlier.

3.According to the passage, your supervisor is most likely your _____________.

A. visitor B. teacher C. workmate D. leader

4.What is the best title for this passage?

A. Getting a New Job. B. Tips on How to Work.

C. The First-day Work. D. The Importance of Co-workers.

There are many American expressions about insects--- like bees, for example. Bees are known as very hard workers. They appear to be busy, moving around their homes, or hives. So you might say you were as busy as a bee if you spent your weekend cleaning your house. In fact, you might say your house was a beehive of activity if your whole family was helping you clean. You also might say you made a beeline for something if you went there right away. When we go to see a movie, my friend always makes a beeline for the place where they sell popcorn .

Here is an expression about bees that is not used much any more, but we like it anyway. We think it was first used in the 1920s. If something was the best of its kind, you might say it was the bee’s knees. Now, we admit that we do not know how this expression developed. In fact, we do not even know if bees have knees!

If your friend cannot stop talking about something because she thinks it is important, you might say she has a bee in her bonnet. If someone asks you a personal question, you might say “that is none of your beeswax”. This means none of your business.

Speaking of personal questions, there is an expression when their children ask, “Where do babies come from?” Parents who discuss sex and reproduction say this is talking about the birds and bees.

Butterflies are beautiful insects, but you would not want to have butterflies in your stomach. That means to be nervous about having to do something, like speaking in front of a crowd. You would also not want to have ants in your trousers. That is, to be unable to sit still.

1.If you make a beeline for something, you _____ .

A. are as busy as a bee B. go quickly and directly towards it

C. always go to the same place D. buy something at a certain place

2.The underlined expression “ it is the bee’s knees” ______ .

A. is not used at all now B. was first used in the 1820s

C. reminds us that bees have knees D. means “it is very good”

3. If you ask your American friend Jack “How old is your wife?” he may say “_____.”

A. It is none of your beeswax B. You have a bee in your bonnet

C. It is the bee’s knees D. You are talking about the birds and bees

4. When you have butterflies in your stomach, you _____ .

A. are too sick to sit still B. have ants in your trousers

C. are nervous about something D. have a stomachache

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