Alaska’s Arctic lakes now freeze later and melt earlier in the year than in 1950，leaving them easy to suffer water loss from evaporation(蒸發(fā))and possibly adding to local warming，a new study finds．The winter ice season near Barrow，Alaska，is shorter than in 1950，researchers reported Jan.30 in the journal The Cryosphere.

Lake ice is also thinner each winter．The scientists surveyed 402 lakes on the North Slope，where permafrost (permanently frozen ground)and shallow lakes dominate the areA． In 2011，the lake ice was 38 percent thinner than in 1950，and 22 percent fewer lakes froze through to their bottoms．

“When we saw the actual numbers we were shocked at how dramatic the change has been，”lead study author Cristina Surdu，of the University of Waterloo in Canada，said in a statement．Surdu and her co-authors analyzed the changes in lake—ice thickness and ice cover with satellite images and climate model simulations(satellite images are only available from 1991)．

The climate models suggest the Arctic lakes froze almost six days later and broke up about 18 days earlier in the winter of 2011 compared with the winter of 1950．“The changes in ice and the shortened winter affect Northern communities that depend on ice roads to transport goods，”Surdu saiD． For example，every winter，oil companies build roads over frozen lakes to carry supplies to Prudhoe Bay．

“The dramatic changes in lake ice may also contribute to further warming of the entire region，because open water on lakes contributes to warmer air temperatures，”Surdu saiD． The Arctic is warming twice as fast as the rest of the planet，for reasons that may include its layered atmosphere，which traps heat，and the loss of sea ice and snow cover，which help reflect the sun’s energy when present．

1.What does the text mainly tell us?

A． Arctic 1akes now freeze earlier and melt 1ater．

B． Alaska’s local warming is decreasing sharply．

C． Arctic lakes are losing ice．

D． Arctic lakes hold more flesh water than before．

2.According to the text，the great changes of Alaska’s Arctic lakes ________．

A． are totally beyond Surdu’s expectations

B． are completely within Surdu’s expectations

C． come as no surprise to Surdu and her co-authors

D． come as a great excitement to Surdu

3.How many days was the winter ice season of Arctic 1akes in 2011 shorter than that in 1950?

A． 6 days．

B． 12 days．

C． 18 days．

D． 24 days．

4.What is the last paragraph mainly about according to Surdu?

A． What reflects the sun’s energy．

B． How its layered atmosphere traps heat．

C． Why our planet is warming．

D． Why the Arctic region is becoming warmer．

練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語 來源：2015-2016學(xué)年遼寧沈陽第二中學(xué)高二12月月考英語試卷（解析版） 題型：閱讀理解

“Get your hands off me, I have been stolen,” the laptop, a portable computer, shouted. That is a new solution to laptop computer theft: a program that lets owners give their property a voice when it has been taken.

The program allows users to display alerts (警報(bào))on the missing computer’s screen and even to set a spoken message. Tracking software for stolen laptops has been on the market for some time, but this is thought to be the first that allows owners to give the thief a piece of their mind.

Owners must report their laptop missing by logging on to a website, which sends a message to the model: a red and yellow “l(fā)ost or stolen” banner pops up on its screen when it is started. Under the latest version(版本) of the software, users can also send a spoken message.

The message can be set to reappear every 30 seconds, no matter how many times the thief closes it. “One customer sent a message saying, ‘You are being tracked. I am right at your door’,” said Carrie Hafeman, chief executive of the company which produces the program, Retriever.

In the latest version, people can add a spoken message. The default （系統(tǒng)設(shè)定）through the computer’s speakers is: “Help, this laptop is reported lost or stolen. If you are not my owner, please report me now.”

The Retriever software package, which costs $29.95 (￡21) but has a free trial period, has the functions of many security software programs. Owners can remotely switch to an alternative password immediately if they fear that the thief has also got hold of the access details.

If a thief accesses the internet with the stolen laptop, Retriever will collect information on the internet service provider in use, so that the police can be alerted to its location.

Thousands of laptops are stolen every year from homes and offices, but with the use of laptops increasing, the number stolen while their owners are out and about has been rising sharply.

Other security software allows users to erase data remotely or lock down the computer.

1.The expression “to give the thief a piece of their mind” can be understood as “_______”.

A. to give the thief an alert mind

B. to express the owners’ anger to the thief

C. to remind the thief of his conscience(良心)

D. to make the thief give up his mind

2.Different from other security software, Retriever can ______.

A. record the stealing process

B. help recognize the lost laptop

C. lock down the computer remotely

D. send a spoken message

3.One function of the program is that it allows the owner to ______ at a distance.

A. change some access details for switching on the laptop

B. turn on the laptop by using the original password

C. operate the laptop by means of an alternative password

D. erase the information kept in the stolen laptop

4.Which of the following can best summarize the main idea of the passage?

A. With no Retriever, thousands of laptops are stolen every year.

B. A new software provides a means to reduce laptop theft.

C. Retriever has helped to find thieves and lost computers.

D. A new program offers a communication platform with the thief.

查看答案和解析>>

科目：高中英語 來源：2016屆安徽宿松縣涼亭中學(xué)上學(xué)期高三第三次月考英語試卷（解析版） 題型：七選五

根據(jù)短文內(nèi)容，從短文后的選項(xiàng)中選出能填入空白處的最佳選項(xiàng)。選項(xiàng)中有兩項(xiàng)為多余選項(xiàng)。

●Does failure really exist?

If you believe you have failed, then you have. If you believe you don’t have the ability to succeed, then you don’t. 1. The moment you decide to give up or stop working toward your goals, failure is born.

● 2.

Most people give themselves an out without even realizing it. They are willing to work hard on reaching their goals, but only until the going gets too rough or their energy dies down. Don’t do that! 3. Never quit, never admit failure, and never lose heart.

●Don’t believe in a clear finish line for goals.

It’s a good idea to set a general timeline, but remember that something will be beyond your control. 4. If you lock yourself into a given timeline, you might make yourself feel like a failure! Instead, get a general idea of when you’d like your goal to be completed. Then take it one day at a time and focus on making progress instead of reaching the finish line in as little time as possible.

●Be sure that you don’t see difficulties as failures.

Difficulties mean only one thing: it’s not time for your goal to be completed yet. That’s it! It doesn’t mean you failed; it doesn’t mean you’re weak; it doesn’t mean you’ll never achieve your goals. 5. You’ve got to keep moving forward and find a way over, around, or through the difficulties.

A. Never give up on yourself.

B. Failure only exists in your own mind!

C. That’s exactly how failure makes us feel.

D. It simply means you have not done enough yet.

E. You can never say exactly when your goal will be reached.

F. Instead, make up your mind to make your goal happen, no matter what!

G. Work hard towards your goal, and you will be likely to get good results.

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年河南陜州中學(xué)高二上第二次精英對(duì)抗賽英語試卷（解析版） 題型：閱讀理解

By today's standards, my mobile phone is pretty rubbish. It's a Nokia 1616. If that doesn't mean much to you (it's not the kind of phone you see advertised on television), all you need to know is that it's a small, not very heavy device with which you can send and receive telephone calls and text messages. It also has a very handy torch on the top for when you can't find your keys, or when you drop something on the floor in the cinema. Other than that, my phone doesn't do much. Well, it has an alarm, and it probably has a calculator and things like that, but it's nothing compared to a smartphone. Why would I want one of those?

I have often been told that the big advantage of having a smartphone is that "you can do everything with them!" But when was the last time you saw someone doing "everything" with a smartphone? Okay, so they may have an endless list of functions, but generally they are used for checking social networking sites, playing games, and receiving and replying to emails. I'm happy just doing all of those things at home on my laptop.

As far as I can tell, the best thing about having a smartphone is that you can be connected to the Internet all the time. Don't get me wrong, I love the internet, but I just don't see the point of constantly being online. I can't remember the last time I received a Facebook update which was so very urgent that I had to read it as soon as it appeared, and I can't imagine ever having a job which was so important that I would need to read work-related emails immediately. I would think that if someone needed me urgently, they would just ring me rather than send an email. And my trusty Nokia can manage that.

One of the most peculiar（獨(dú)特的）effects of the smartphone is, in my opinion, the newly-found addiction to maps and navigation (導(dǎo)航) systems. Is there anything more boring than knowing exactly where you are all of the time?! How do you get to know an area if you don't get lost there a few times? And if you are dependent on online maps, what happens to those great places you find just by chance? You can't exactly find out from Google maps the journey from "here" to" that hidden cafe with the tasty-looking cakes" , or to "that pond next to the church which looks really pretty in the evening sun. " It is, of course, true that we all occasionally need to be pointed in the right direction, but I find that there are often real life humans you can ask.

There are many benefits of having a very basic mobile phone, like the fact that it cost me about twenty pounds, and that I don't have to worry too much about it being stolen .But the main benefit has to be the fact that it provides me with the word 'greatest excuse for my bad habits’. Whether it's turning up late to events ,or getting lost on a trip, or missing buses or trains ,or forgetting about an appointment at work ,I'm pretty sure I'm covered with the following explanation: “I’m really sorry, I don't have a smartphone."

1.The writer uses his Nokia 1616 mainly to _______.

A. play online games

B. do calculating work

C. check social network sites

D. make calls and text messages

2.It can be inferred from the above passage that_______.

A. work-related emails should be answered immediately

B. a laptop and a smartphone share many functions

C. smartphones should always be connected to the net

D. a Facebook update is usually very important

3.According to the passage, if you use navigation systems, you may _____

A. miss some really wonderful places

B. find a boring trip actually exciting

C. be persuaded to eat in a certain café

D. be misled to a totally wrong place

4.The writer’s purpose for writing this article is to______

A. explain why he doesn’t want a smartphone

B. warn readers of the risks of using smartphones

C. complain about the troubles caused by smartphones

D. inform readers of the latest development of mobile phones

查看答案和解析>>

科目：高中英語 來源：2016屆江西省、九江一中高三上學(xué)期期中英語試卷（解析版） 題型：完形填空

I lost my elderly mother a few weeks ago．Actually，my mother had fallen over during the night and had not been able to again．She had woken up the neighbors by banging on the wall．The called an ambulance，which took her to the hospital.

My mother has thought that hospitals are a real horror．She believes that doctors and hospitals give you diseases．My father went to hospital a year ago，and after a few weeks，he ．The fact that he was also in the final________of lung cancer was certainly related，but by my mother's logic，my father's death was with the hospital.

When a neighbor me up and told me that my mother had been taken off in an ambulance，the first thing I did was similar，which was to ring Queen Elizabeth Hospital．The paramedics(護(hù)理人員) had told my neighbor that my mother would ________be taken there， I was told that no one by that name had been ，so they gave me the numbers of two other West Midland hospitals．Both of them also ________ that they were holding my mother．I rang the and asked them to find her，but the nice officer said he could only do that if she had been reported as a(n) person.

It took six calls to my mother．She had been in Queen Elizabeth Hospital all along，but because their computer system hadn't been updated overnight，there was no record of her ．My mother had spent more than a in the hospital when it turned out there was nothing with her．I managed to get her out within 10 days，but only by agreeing that in the future，she would live downstairs．In return，the hospital said they would for a social worker to visit the house three or four rimes a day.

Luckily，my mother is safe．Thank all the people who have given their help to us.

1.A． wake up B． get up C． stay up D． light up

2.A． neighbors B． strangers C． relatives D． friends

3.A． out B． up C． away D． from

4.A．consequently B． occasionally C． always D． rarely

5.A． final B． special C． fatal D． strange

6.A． passed away B． went away C． passed by D． went by

7.A． measures B． cures C． stages D． years

8.A． connected B． faced C． equipped D． pleased

9.A． cheered B． rang C． scolded D． held

10.A． willingly B． happily C． likely D． easily

11.A． but B． and C． when D． or

12.A． adopted B． admitted C． adjusted D． adapted

13.A． refused B． said C． denied D． insisted

14.A． police B． family C． doctors D． nurses

15.A． old B． dead C． missing D． sick

16.A． rescue B． locate C． comfort D． persuade

17.A． illness B． arrival C． checkout D． medicine

18.A． month B． year C． week D． day

19.A． interesting B． wrong C． special D． vital

20.A． allow B． answer C． arrange D． call

查看答案和解析>>

科目：高中英語 來源：2016屆江西省南昌市高三上學(xué)期第一次月考英語試卷（解析版） 題型：閱讀理解

Guide to Stockholm University Library

Our library offers different types of studying places and provides a good studying environment．

Zones

The library is divided into different zones．The upper floor is a quiet zone with over a thousand places for silent reading，and places where you can sit and work with your own computer．The reading places consist mostly of tables and chairs．The ground floor is the zone where you can talk．Here you can find sofas and armchairs for group work．

Computers

You can use your own computer to connect to the wi-fi specially prepared for notebook computers; you can also use library computers，which contain the most commonly used applications，such as Microsoft Office．They are situated in the area known as the Experimental Field on the ground floor．

Group-study Places

If you want to discuss freely without disturbing others，you can book a study room or sit at a table on the ground floor．Some study rooms are for 2-3 people and others can hold up to 6-8 people．All rooms are marked on the library maps．

There are 40 group-study rooms that must be booked via the website．To book，you need an active University account and a valid University carD． You can use a room three hours per day，nine hours at most per week．

Storage of Study Material

The library has lockers for students to store course literature．When you have obtained at least 40 credits，you may rent a locker and pay 400 SEK for a year’s rental perioD．

Rules to be Followed

Mobile phone conversations are not permitted anywhere in the library．Keep your phone on silent as if you were in a lecture and exit the library if you need to receive calls．

Please note that food and fruit are forbidden in the library，but you are allowed to have drinks and sweets with you．

1.Library computers on the ground floor ．

A． help students with their field experiments

B． contain software essential for schoolwork

C． are for those who want to access the wi-fi

D． are mostly used for filling out application forms

2.A student can rent a locker in the library if he ．

A． can afford the rental fee

B． attends certain courses

C． has nowhere to put his books

D． has earned the required credits

3.What should NOT be brought into the library?

A． Mobile phones．

B． Orange juice．

C． Candy．

D． Sandwiches．

查看答案和解析>>

科目：高中英語 來源：2015-2016學(xué)年河北承德市高一上學(xué)期第一次月考英語試卷（解析版） 題型：閱讀理解

What is the hottest topic at your school recently? In Taiyuan No. 55 Middle School, it’s money.

The school held an activity called “making money” last weekend. About 200 Junior 1 and Junior 2 students were divided into 30 teams. They went out to make money by selling things.

What did they choose to sell? Some sold newspapers; some chose bottled water; some sold environmentally friendly shopping bags and bamboo baskets.

Hu Qing’s team decided to sell some useful books in front of the Children Activity Center. They thought parents would like to buy the books for their children. But unfortunately, they met urban management officers (城管). The officers asked them to leave. “We played hide-and-seek (捉迷藏) with the officers for the whole morning” said Hu. “Finally we had to give up.”

Wang Bing and her team sold ice cream in a square. They didn’t meet any officers. But few people were interested in what they were selling. The team then put up a board saying “For Country Kids”. It worked. More people came to their stall (小攤). A foreigner even gave them 100 yuan. “He didn’t want any change. He said he wanted to help the children,” said Wang. “We were touched.” Later that day they gave the 100 yuan and more to the “Project Hope” office.

Meng Zhaoxiang and his team were luckier. They sold all their cakes in four hours, spending 39.5 yuan and getting back 80 yuan. They made 40.5 yuan. “It was not easy to make the money,” said Meng. “Some people just looked. Others just tasted but didn’t buy. Now I know how hard it is for our parents to make the money we need to lead happy lives.”

1.______ took part in the activity.

A. Some teachers

B. About 200 of Junior 1 and Junior 2 students

C. About 200 students of the three grades

D.About200 Junior 1 students

2.Hu Qing’s team finally gave up because ______.

A. the parents didn’t like to buy the books

B. the Children Activity Center was too crowded

C. the officers didn’t allow them to sell anything there

D. the team played the game of the hide-and-seek the whole morning

3.Why did more people come to Wang Bing’s stall at last?

A. The people were willing to help country kids.

B. A foreigner came up and helped them.

C. The team put up a magic board.

D. The people were interested in their ice cream.

4.According to the passage the students learn ______.

A. it’s impossible for them to make money

B. it’s very important for them to make a living

C. it’s not easy for their parents to make money

查看答案和解析>>

科目：高中英語 來源：2016屆山西省高三上學(xué)期期中考前檢測英語試卷（解析版） 題型：閱讀理解

The human body is designed to move. But modern lifestyles and office jobs rarely give us the chance to move around. As we know. we're while we're eating; we sit in the car and we sit while we watch TV. And many of us sit for many hours at work.

New research shows that sitting less than three hours a day might extend your life by two years. Peter Katzmarzyk，a scientist at the University of Louisiana in the southern United States，says that sitting is ubiquitous in our lives，meaning it is something we do all the time，everywhere.

However，Mr. Katzmarzyk says that does not mean you can sit for the rest of your waking hours. He also says you may exercise often，“We can't throw away physical activity. It's extremely important. We have 60 years of research showing us that. ”

Mr. Katzmarzyk and his coi leagues are part of a new generation of researchers studying how sitting all day affects length of life. “Studies that have assessed the relationship between sitting and mortality(死亡率)or television viewing and mortality are very rare. There's only been a few of them，actually five or six now，in the last four or five years. ”They found that cutting television time to less than two hours a day could add one-point four years to life.

Luckily，change is already coming to some offices，especially in the design of desks. A “standing desk”lets people stand while they work. Another new design is called the “treadmill desk. ” A treadmill is an exercise machine that lets you walk in one place. Even some U. S. schools are beginning to experiment with desks that are part bicycle to keep children moving. That's one of the strategies that many companies are using now.

Mr. Katzmarzyk also says studying this problem has inspired his team to make a few changes in their own lives.

1.Which view agrees with the opinion of Mr. Katzmarzyk?

A． Sitting too long may help increase one's life.

B． Exercise is important and don't sit too long.

C． Watching TV is bad，but can broaden one's horizons.

D． Stopping watching TV is a necessary but hard task.

2.What does Mr. Katzmarzyk think of his study in Paragraph 4?

A． It's a ly new area of study.

B． It's a hot subject studied by experts.

C． It's a study that begins too late.

D． It's not ignored by many experts.

3.Why are the desks of all kinds designed for those who sit more?

A． To give them more comfort.

B． To improve their work efficiency.

C． To offer them the chance to exercise.

D． To seek pleasure while working.

查看答案和解析>>

同步練習(xí)冊(cè)答案