Some people bring out the best in you in a way that you might never have fully realized on your own.My mother was one of those people.
My father died when I was one-year-old.While I was growing up, we led a very hard life, but my mom gave me a lot of love.Each night, she seated me on her lap and, spoke the words that would change my life, "Kemmons, you are sure to be a great man and you can do anything in life if you work hard enough to get it."
At fourteen, I was hit by a car and the doctors said that I would never walk again.Every night my mother spoke to me in her gentle, loving voice, telling me whatever those doctors said, I could walk again if I wanted to.She drove that message so deep into my heart that I finally believed her.A year later, I walked on my own to school!
When the Great Depression broke out, my mother lost her job.Then I left school to support the two of us.At that moment I decided never to be poor again.
Over the years, I experienced a lot of business success.But the real turning point happened on a vacation I took with my wife and five kids in 1951.I was dissatisfied with the second-class hotels available for families and was very angry that they charged an extra $2 for each child.That was too expensive for an ordinary American family.I told my wife that I was going to open a motel （汽车旅馆） for families that would never charge extra money for children.Many people did not believe me at that time.
Not surprisingly, mom was my strongest supporter.As in any business, I experienced a lot of difficulties.But with my mom's words in my heart, I never doubted I would succeed.Fifteen years later, I had the largest hotel system in the world—Holiday Inn.In 1979 my company had 1,759 inns in more than fifty countries with an income of $l billion a year.
You may not have started out life in the best situations.But if you find a task in life worth working for and believe in yourself, nothing can stop you.

1.
What Kemmon's mother often told him during his childhood was____.
1. A.
  caring
2. B.
  moving
3. C.
  encouraging
4. D.
  interesting
2.
Who played the most important role in making the author walk back to school again?
1. A.
  Doctors.
2. B.
  Nurses.
3. C.
  His friend.
4. D.
  His mom.
3.
What caused Kemmon to start a motel by himself?
1. A.
  His terrible experience in the hotel.
2. B.
  His wife's suggestion.
3. C.
  His previous business success.
4. D.
  His mom's support.
4.
Which of the following best describes Kemmon's mother?
1. A.
  Modest, helpful and hard-working.
2. B.
  Loving, supportive and strong-willed.
3. C.
  Careful, beautiful and helpful.
4. D.
  Strict, sensitive and supportive.
5.
Which of the following led to Kemmon's success?
1. A.
  Self-confidence, hard work, higher education and a poor family.
2. B.
  Mom's encouragement, clear goals, self-confidence and hard work.
3. C.
  Clear goals, mom's encouragement, a poor family and higher education.
4. D.
  Mom's encouragement, a poor family, higher education and opportunities.

Diary of a Do-It-Yourself Book
This book based on Greg Hefley's own "diary" lets kids express themselves in an exciting way.In the book, kids will be asked: What was the best dream you have ever had? The worst thing you have ever eaten? The best secret you have ever heard? This Do-It-Yourself Book is unique and special because it has blank pages for readers to write their own stories and keep their own diaries.
Author:       Jeff Kinney
List Price:     $10.95
Price:         $6.57      Buy it on Amazon.com.
You save:      $4.38（40%）
Train to Somewhere
Marianne, heading west with fourteen other children on a train, is sure her mother will show up at one of the stations along the way. Stop after stop goes by, and there is no sign of her mother in the crowds that come to look over the children. No one shows any interest in adopting shy Marianne, either. But th at is all right. She has to he free for her mother to claim her. Then the train stopped at its final stop, a town called Somewhere…
Author:        Eve Bunting
List Price:      $6.95
Price:        $6.95      Buy it on Amazon.com.
You save:      $0.00（0%）
Chinese Children's Favorite Stories
This volume of beloved Chinese stories contains a delightful selection from the store of Chinese legend. Discover many delightful animal characters as well as Change and Guan Yin. Retold for an international audience, the stories with beautiful pictures will give children aged ix to ten in other countries a chance to learn about both the tradition and culture of China.
Author:         Mingmei Yip
List Price:      $18.95
Price:         $12.89      Buy it on Amazon.com.
You save:      $6.06（32%）
The Way Science Works
The perfect introduction to show how science explains the world around us! Eye-opening experiments and extraordinary photography bring science to life.Discover science in action from the principles that explain everyday facts to the theories behind the technology in today's fast-moving world. Full of facts about famous scientists, technology news and more.
Author:        Robin Kerrod
List Price:      $24.99
Price:         $16.49      Buy it on Amazon.com.
You save:      $8.50（34%）

1.
Diary of a Do – It – Yourself Book is different from other books because you can .
1. A.
  ask the author questions
2. B.
  write your own stories in the book
3. C.
  have a chance to see beautiful photos
4. D.
  read many interesting stories about the author
2.
Amazon.com gives no discount on .
1. A.
  Diary of a Do-It-Yourself Book
2. B.
  Train to Somewhere
3. C.
  Chinese Children’s Favorite Stories
4. D.
  The Way Science Works
3.
Based on Train to Somewhere, how many children head west on the train.
1. A.
  15.
2. B.
  14.
3. C.
  13.
4. D.
  16.
4.
Chinese Children's Favorite Stories is written for____
1. A.
  Chinese children aged 6 to 10
2. B.
  teenagers in other countries
3. C.
  junior students in other countries
4. D.
  foreign children aged 6 to 10
5.
Whose book would you like to read if you are interested in science and technology?
1. A.
  Jeff Kinney’s.
2. B.
  Eve Bunting's.
3. C.
  Mingmei Yip’s.
4. D.
  Robin Kerrod’s.

Treatment for HIV has become more widespread, especially in poorer countries. It's also become cheaper, as medicine companies have lowered their prices for life-saving anti-retroviral drugs(抗逆转录病毒药物). But these drugs are still expensive and many countries are looking to create the biggest impact with limited resources. That's where World Health Organization guidelines come in, says Rochelle Walensky, a disease researcher from Harvard.
Walensky and her colleagues used computer programs to model the most cost-effective disease interventions(干预), as well as collected data from clinics in Africa and India about what works best. They found that among the choices of what to do first, earlier anti-retroviral therapy (疗法)improved five-year survival dramatically and resulted in the longer life expectancy. But cost-effective doesn't always mean affordable, especially for governments in poor countries. Countries still have to make difficult choices about how much treatment they can afford.
People in Nairobi, Kenya on Thursday, Dec. 9, 2010, protest a potential free trade area agreement between the EU and India that could see cheap anti-AIDS drugs phased out（逐步淘汰）. However, Walensky notes that first-line anti-retrovirals—those medicine given to newly diagnosed patients that can keep away from symptoms for years - are much cheaper than they were a decade ago. "Second-line therapy have come down quite a bit but not to the level of first-line and countries are having a hard time affording them and increasingly over time, people are going to fail first-line therapy and they're going second-line therapy and then, eventually, they're going to need third-line therapy, some of them."
According to Walensky, history has shown that drug prices can come down when international pressure is applied to drug makers. But for now, she says, countries should focus on treating as many people as they can, as early as possible
Her paper is published in the online journal PLoS Medicine.

1.
Which is the best title for the passage?
1. A.
  HIV Has Spread in Poorer Countries
2. B.
  Rochelle Walensky’s Life
3. C.
  International Pressure to Drug Makers
4. D.
  Early HIV Treatment Saves Lives
2.
Which of the following is TRUE according to the passage?
1. A.
  Anti-retroviral drugs have become cheap now.
2. B.
  The cost-effective treatment may be a heavy expense.
3. C.
  Cheap anti-AIDS drugs have been phased out .
4. D.
  First-line therapy deals with the most severe disease.
3.
The research is done by .
1. A.
  using computer programs and collecting data from clinics
2. B.
  giving medicine to newly diagnosed patients with AIDS
3. C.
  urging countries to focus on treating more patients earlier
4. D.
  publishing her paper in the online journal PLoS Medicine
4.
The passage serves as a（n）___________ to Rochelle Walensky 's study.
1. A.
  assessment
2. B.
  comment
3. C.
  introduction
4. D.
  background

Andrew Ritchie, inventor of the Brompton folding bicycle, once said that the perfect portable bike would be “like a magic carpet…You could fold it up and put it into your pocket or handbag”. Then he paused: “But you’ll always be limited by the size of the wheels. And so far no one has invented a folding wheel.”
It was a rare — indeed unique — occasion when I was able to put Ritchie right. A 19th-century inventor, William Henry James Grout, did in fact design a folding wheel. His bike, predictably named the Grout Portable, had a frame that split into two and a larger wheel that could be separated into four pieces. All the bits fitted into Grout’s Wonderful Bag, a leather case.
Grout’s aim: to solve the problems of carrying a bike on a train. Now doesn’t that sound familiar? Grout intended to find a way of making a bike small enough for train travel: his bike was a huge beast. And importantly, the design of early bicycles gave him an advantage: in Grout’s day, tyres were solid, which made the business of splitting a wheel into four separate parts relatively simple. You couldn’t do the same with a wheel fitted with a one-piece inflated （充气的） tyre.
So, in a 21st-century context, is the idea of the folding wheel dead? It is not. A British design engineer, Duncan Fitzsimons, has developed a wheel that can be squashed into something like a slender ellipse （椭圆）. Throughout, the tyre remains inflated.
Will the young Fitzsimons’s folding wheel make it into production? I haven’t the foggiest idea. But his inventiveness shows two things. First, people have been saying for more than a century that bike design has reached its limit, except for gradual advances. It’s as silly a concept now as it was 100 years ago: there’s plenty still to go for. Second, it is in the field of folding bikes that we are seeing the most interesting inventions. You can buy a folding bike for less than £1,000 that can be knocked down so small that it can be carried on a plane — minus wheels, of course — as hand baggage.
Folding wheels would make all manner of things possible. Have we yet got the magic carpet of Andrew Ritchie’s imagination? No. But it’s progress.

1.
We can infer from Paragraph 1 that the Brompton folding bike .
1. A.
  was portable
2. B.
  had a folding wheel
3. C.
  could be put in a pocket
4. D.
  looked like a magic carpet
2.
We can learn from the text that the wheels of the Grout Portable .
1. A.
  were difficult to separate
2. B.
  could be split into 6 pieces
3. C.
  were fitted with solid tyres
4. D.
  were hard to carry on a train
3.
We can learn from the text that Fitzsimons’s invention .
1. A.
  kept the tyre as a whole piece
2. B.
  was made into production soon
3. C.
  left little room for improvement
4. D.
  changed our views on bag design
4.
Which of the following would be the best title for the text?
1. A.
  Three folding bike inventors
2. B.
  The making of a folding bike
3. C.
  Progress in folding bike design
4. D.
  Ways of separating a bike wheel

Dear Customers,
I love slipping (滑落) into a comfortable chair for a long read—as I relax into the chair, I also relax into the author’s words, stories and ideas. The physical book is so elegant that it disappears into the background, and what remains is the author’s world.
Today, we at Amazon are excited to announce Mindle, a wireless, portable reading device with instant access to more than 90,000 books, magazines and newspapers.
We’ve been working on Mindle for more than three years. Our top design objective was for Mindle to disappear in your hands—to get out of the way—so you can enjoy your reading. We also wanted to go beyond the physical book. Mindle is wireless, so whether you’re lying in bed or riding a train, you can think of a book, and have it in less than 60 seconds. No computer is needed—you do your reading directly from the device.
We chose the same wireless technology used in advanced mobile phones. But unlike mobile phones, there are no monthly wireless bills, no service or data plans, and no yearly contracts. There is no software to install (安装，设置)。 We want you to get lost in your reading and not in the technology.
Mindle uses a new kind of display called electronic paper. Sharp and natural with no strong light, reading on Mindle is nothing like reading from a computer screen. Mindle weighs only 10.3 ounces—less than paperback—but can carry two hundred books.
Enjoy learning about Mindle and many thanks!
Jeff Bezos Founder & CEO

1.
This passage most probably is a(n)________.
1. A.
  advertisement
2. B.
  news story
3. C.
  lab report
4. D.
  letter of thanks
2.
From the passage we learn that Mindle is a device which ________.
1. A.
  has neither wires nor weight
2. B.
  is operated by a computer
3. C.
  disappears while you read
4. D.
  can find a book within one minute
3.
With the device, the reader is able to ________.
1. A.
  enjoy reading when driving a car
2. B.
  improve reading skills
3. C.
  gain access to free software
4. D.
  get rid of heavy books made of paper
4.
Different from mobile phones, Mindle________.
1. A.
  has a much more friendly screen
2. B.
  can work in the absence of electricity
3. C.
  doesn’t involve regular bills
4. D.
  is wireless and can be used anywhere.

Last weekend, my kids along with a few other kids from the neighborhood volunteered to help me wash my car. My 10-year-old daughter came up with the idea of washing other people’s cars as well. It was pretty hot outside. She further wanted to give juice for a low cost but not free. I felt happy and decided to help her.
She asked me, “What if we make this ‘a smile car wash’, mommy? ”I couldn’t hold back my tears and encouraged her and other kids to go inside the house and come up with ideas. While I kept myself busy in drying the car, the kids walked up to me with a board of beautiful signs of smiles. They had “Free Car Wash” written on it and the theme of their exercise was “Smile”. It was pretty natural to see a team of kids 5 to 11 years with the task to do something for others.
All that seemed natural and came right from their heart. Nothing seemed to matter to them: their playtime, and then heat outside—they just wanted to help and do something nice in the community!
I helped them make some fresh juice and brought out some waste materials to help clean cars. Passers-by were amazed and one even shouted at them saying “Good kids”. One of them even tried giving them 5 dollars, which they refused. A pretty heart-warming scene!
The following weekend, I saw the idea of the week, the theme of which was “Global Kindness”. I was moved by such wonderful and loving souls. They made me smile!
One of the slogans (标语) on their flag was: “Do not fear! Smile retrievers(挽回者) are here.”

1.
Who raised the idea of washing other people’s cars for free?
1. A.
  The mother
2. B.
  One of the passers-by
3. C.
  The writer’s 10-year-old daughter
4. D.
  One of the writer’s neighbors’ kids.
2.
Why couldn’t the author hold back her tears when she knew her daughter’s idea?
1. A.
  She was moved by her daughter’s kindness.
2. B.
  She felt sorry for those passers-by in hot weather.
3. C.
  She was sorry for not helping the kids.
4. D.
  She thought of too much hardship of the kids.
3.
Why did the kids want to wash others’ cars for free?
1. A.
  They wanted to earn money.
2. B.
  They were asked to do that by their teacher.
3. C.
  They just wanted to help and do something nice in the community.
4. D.
  They wanted to exercise in smiling.
4.
Which of the following did NOT the writer do to help the kids?
1. A.
  She supported the kids’ ideas.
2. B.
  She prepared some fresh juice for the passers-by.
3. C.
  She brought out some waste materials to help the kids.
4. D.
  She gave the kids some money.

MY Chinese friend is going to the US and he is nervous about what to talk about. “Talk about the weather,” is my advice.
“How are you?” is often followed by comments about the weather. “Nice day today.” “Cold/hot enough for you?” “Will it ever stop raining?” “Some winter we’re having.” “Can’t remember a winter/summer so cold/hot.” “Whew, it’s hot out there.”
These introductory statements are often followed by a long conversation entirely about weather conditions. Past, present and – with global warming – speculation (推测) about the future.
Our fascination with weather might seem silly, but the real purpose behind those endless discussions is small talk. Weather’s a safe topic of conversation. As a group, we Americans seem to enjoy chatting with those around us. Whenever we stand in line at the grocery store, we tend to engage in this sort of conversation with other people standing in line with us. If I were seated next to another American on any form of public transport, I’d expect both of us to make some harmless comment about the weather as a way of acknowledging (承认) each other’s presence (存在). At parties, the weather is a common topic, especially with those you are meeting for the first time.
In contrast we are taught to avoid certain topics like religion and politics. Weather is neutral (中性的); you don’t have to have an opinion about it, just make a statement of a fact. What is truly interesting is the fact that we can go on and on about it.
My Chinese friend has a hard time understanding why we put so much effort into this topic – and why I warn him about bringing up much more “interesting” subjects like salaries or how much something costs.
Sometimes it is tricky (复杂的) to wend (行走) one’s way through winding cultural roads, especially those that are never taught in books.

1.
What does the writer suggest her Chinese friend should talk about with people in the US? (No more than two words)
2.
Why do Americans enjoy talking to people around them about the weather, in writer’s opinion? (No more than ten words)
3.
List four topics that people should avoid talking about in the US. ( No more than 5 words)

Research has shown that music has an important effect on one’s body and psyche (心灵). In fact, there is a growing field of health care known as music therapy, which uses music to treat diseases. Even hospitals are beginning to use music therapy. This is not surprising, as music affects the body and mind in many powerful ways.
Research has shown that quick music can make a person feel more alert, while slow music can produce a calm, deep thinking state. Also, research has found that music can change brainwave activity levels. This can help the brain to change speeds more easily on its own as needed, which means that music can bring lasting benefits to your state of mind, even after you’ve stopped listening.
Breathing and heart rates can also be influenced by music. This can mean slower breathing, slower heart rate. This is why music and music therapy can help reduce the damaging effects of long-term stress, greatly promoting (促进) not only relaxation, but health.
Music can also be used to bring about a more positive state of mind by helping to keep worries away. Music has also been found to bring many other benefits, such as lowering blood pressure and reducing the risk of strokes. It is no surprise that so many people are considering music as an important tool to help the body become or stay healthy.

1.
What can we infer about music therapy?
1. A.
  It is a type of music.
2. B.
  It is a research about music.
3. C.
  It is a kind of musical effect on diseases.
4. D.
  It is the use of music method to help treat diseases.
2.
According to the second paragraph, we can know that ________.
1. A.
  music with different speeds has different effects
2. B.
  quick music is not good for one’s health
3. C.
  slow music can help one to think more calmly and slowly
4. D.
  music will have less benefit after one stops listening
3.
The reason why music can help deal with stress is that ________.
1. A.
  it is used by many hospitals
2. B.
  it can help change brainwaves
3. C.
  it does good to breathing and heart rates
4. D.
  it can bring a more positive state of mind
4.
According to the passage, music can help deal with all the following EXCEPT ________.
1. A.
  nervousness
2. B.
  mind illnesses
3. C.
  strokes
4. D.
  high blood pressure

London has a new magazine. But it’s not printed on paper. Everyone who has a television can receive it because it is on TV.
In order to read this magazine you have to have a decoder. Each page of it is numbered, so you only have to dial the number to choose which subject you want to read about. There’s a wide choice--- everything is included from cooking to the latest sports news.
If you want to read the news, the first thing you have to do is to turn to the index page which has an easy-to-remember page number, 100 for example. Then you start choosing what you want to read. The news is on pages 101 to 109, so you push out the numbers and the news appears written across your screen. Perhaps you want to go out in the afternoon, so you press 181, and a brightly colored weather map appears on the screen. But the weather is terrible so you decide to go shopping and dial 162 for a list of the week’s best bargains. But should you drive or take the train ? To answer the question you only have to press 189 for the traffic report. It’s very simple to use. But probably the best thing about the service is that it’s being updated all the time. Journalists type new material directly onto the screen and whole pages of the magazine can be replaced in minutes.
London has already had three services. One, transmitted（传输）by ITV, is called ORACLE, while the other two, on BBC, are called CEEFAX, because they let you see facts. Although CEEFAX and ORACLE have been operating for some time, they have not been well publicized. BBC engineers do not think that their idea will ever replace books and newspapers because they can be taken with you everywhere. But many people agree that this is a breakthrough as great as the invention of printing, which could change not just our reading habits but our whole way of life.

1.
What is unusual about the mew magazine in London?
1. A.
  You can find any subject you want in it.
2. B.
  No paper is used to print the magazine.
3. C.
  There 1,000 page numbers in the index.
4. D.
  The speed of transmitting is astonishing.
2.
It’s clearly seen from the passage that ________.
1. A.
  it takes long for the service of the magazine to be updated
2. B.
  most of the postmen will be out of work someday
3. C.
  the readers can get all kinds of information without leaving home
4. D.
  everyone can read the magazine if there is a television at hand
3.
According to the passage, the “decoder” is used to help people to ________.
1. A.
  read the information transmitted by TV signals
2. B.
  broadcast special TV programs at home and abroad
3. C.
  dial the number to choose which subject you want to read about
4. D.
  find the exact page in which you can get information you need
4.
The passage is mainly about .
1. A.
  a new magazine printed in London
2. B.
  a popular TV program with three services
3. C.
  a great breakthrough in printing
4. D.
  an up-to-date way of keeping up to date

The average college student in America spent an estimated seven hundred dollars on textbooks last year. The National Association of College Stores reported more than five billion dollars in sales of textbooks and course materials. Association spokesman Charles Schmidt says electronic textbooks now represent just two to three percent of sales. But he says that is expected to reach ten to fifteen percent by 2012. Online versions are now available for many of the most popular college textbooks. E-textbooks can cost half the price of a new print textbook. But students usually lose access after the end of the term. And the books cannot be placed on more than one device (装置) so they are not easy to share.
So what do students think of e-textbooks? Administrators at Northwest Missouri State University wanted to find out. Earlier this year they tested them with five hundred students in twenty classes. The university is unusual. It not only provides laptop computers to all seven thousand of its full-time students. It does not require students to buy their textbooks either. They rent them to save money. The school aims to save even more by moving to e-textbooks. The students in the survey reported that downloading the books from the Internet was easy. They liked the idea of carrying lighter backpacks. And fifty-six percent said they were better able to find information. But most found that using e-textbooks did not change their study habits. And sixty percent felt they read more when they were reading on paper. In all, almost half the students said they still liked physical textbooks better. But the survey found that cost could be a big influence. Fifty-five percent said they would choose e-textbooks if using them meant their textbook rental fee would not increase. Roger Von Holzen heads the Center for Information Technology in Education at Northwest Missouri State. He tells us that administrators are disappointed with the e-textbooks now available because the majority are not interactive. He thinks growth will come when more digital books include video, activities, games and other ways to interact with the information. The technology is improving. But for now, most of the books are just words on a screen.

1.
The passage mainly tells us about ________.
1. A.
  the development of e-textbooks
2. B.
  different attitudes towards e-textbooks
3. C.
  the sales of textbooks and course materials
4. D.
  the differences between e-textbooks and physical text-books
2.
According to the survey, over half of the students think e-textbooks ________.
1. A.
  can be rented for less money
2. B.
  help in finding more information
3. C.
  are convenient to carry around
4. D.
  help them do better in their lessons
3.
It can be inferred from the passage that e-textbooks ________.
1. A.
  will replace physical textbooks
2. B.
  are available at any time
3. C.
  have a very bright future
4. D.
  still have a lot to improve

0 7709 7717 7723 7727 7733 7735 7739 7745 7747 7753 7759 7763 7765 7769 7775 7777 7783 7787 7789 7793 7795 7799 7801 7803 7804 7805 7807 7808 7809 7811 7813 7817 7819 7823 7825 7829 7835 7837 7843 7847 7849 7853 7859 7865 7867 7873 7877 7879 7885 7889 7895 7903 151629

What Kemmon's mother often told him during his childhood was____.

Who played the most important role in making the author walk back to school again?

What caused Kemmon to start a motel by himself?

Which of the following best describes Kemmon's mother?

Which of the following led to Kemmon's success?

Diary of a Do – It – Yourself Book is different from other books because you can .

Amazon.com gives no discount on .

Based on Train to Somewhere, how many children head west on the train.

Chinese Children's Favorite Stories is written for____

Whose book would you like to read if you are interested in science and technology?

Which is the best title for the passage?

Which of the following is TRUE according to the passage?

The research is done by .

The passage serves as a（n）___________ to Rochelle Walensky 's study.

We can infer from Paragraph 1 that the Brompton folding bike .

We can learn from the text that the wheels of the Grout Portable .

We can learn from the text that Fitzsimons’s invention .

Which of the following would be the best title for the text?

This passage most probably is a(n)________.

From the passage we learn that Mindle is a device which ________.

With the device, the reader is able to ________.

Different from mobile phones, Mindle________.

Who raised the idea of washing other people’s cars for free?

Why couldn’t the author hold back her tears when she knew her daughter’s idea?

Why did the kids want to wash others’ cars for free?

Which of the following did NOT the writer do to help the kids?

What does the writer suggest her Chinese friend should talk about with people in the US? (No more than two words)

Why do Americans enjoy talking to people around them about the weather, in writer’s opinion? (No more than ten words)

List four topics that people should avoid talking about in the US. ( No more than 5 words)

What can we infer about music therapy?

According to the second paragraph, we can know that ________.

The reason why music can help deal with stress is that ________.

According to the passage, music can help deal with all the following EXCEPT ________.

What is unusual about the mew magazine in London?

It’s clearly seen from the passage that ________.

According to the passage, the “decoder” is used to help people to ________.

The passage is mainly about .

The passage mainly tells us about ________.

According to the survey, over half of the students think e-textbooks ________.

It can be inferred from the passage that e-textbooks ________.

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