评论
打印
B
Which tablet computer should YOU be buying: They are this year's must have... and
there's a style to suit everyone?
Best for young children
LeapPad Explorer 2, ￡68
Aimed at children between three and nine (though a nine-year-old might find it a little simple), it comes in pink or blue and with five built-in education games (you can buy more). Besides, the LeapPad does not allow access to the internet — so it is impossible for your child to stumble across anything inappropriate.
Pros: The education games are well-designed, the built-in video camera is a fun way to play at being a film director.
Cons: Some of the games are shockingly expensive. And the power adaptor is not included.
Best for teenagers
iPad 4th generation, ￡399-￡659
The iPad is still the market leader, and for good reason. If the teenager in your house enjoys playing computer games, the latest offering from Apple is the one to choose.
Pros: No other tablet can compete with the near one million ‘apps’ (the name Apple created for specially-designed downloadable programs) available for the iPad. Simple to use, even for those who usually struggle with technology.
Cons: Considerably more expensive than most competitors.
Best for working parents
Microsoft Surface, ￡399-￡559
Tablets are brilliant for leisure — but what if you want to do a bit of work? No tablet can yet compete with a full-size laptop computer, but this is the only tablet that allows you to use Microsoft Word, Excel and Powerpoint (they are all pre-installed and included in the price) and you can buy a pretty lovely mini- keyboard for typing letters and emails, which also doubles up as the cover.
Pros: The Surface is good for watching movies — a bonus when stuck in the airport on a business trip — and surfing the internet.
Con: The keyboard is an expensive add-on — costing up to ￡109. It might be cheaper to buy a laptop (though a tablet is much smaller and lighter).
Best for bookworms
Amazon Kindle Paperwhite, ￡109
Nearly all tablets let you download books. It's a great way to take a mountainous pile of hardbacks on holiday without stuffing your suitcase.
But most tablets have a shiny screen —which can be very distracting when you're trying to read. The Paperwhite is different: its matt screen and crisp black lettering imitate the look of words on paper brilliantly. And yet you can still read the words in the dark.
Pros: Easy on the eye, excellent battery life, 180,000 free books (if you subscribe to the Amazon Prime customer loyalty service) plus hundreds of thousands more to buy.
Cons: No TV, films, games, internet or camera.
70. The underlined phrase ‘stumble across’ most probably means ‘___________’.
A. quarrel with B. meet with C. compare with D. compete with
71. Which of the following about Surface is TRUE?
A. You have to pay extra to install Microsoft Word.
B. The keyboard can serve as a cover.
C. The keyboard will not add to the cost of the tablet computer.
D. You cannot watch movies or surf the internet with it.
72. If you are a game lover, which tablet is least likely to be your choice?
A. Amazon Kindle Paperwhite. 2. B. iPad 4th generation
C. Microsoft Surface. D. LeapPad Explorer
73.If you want to add something to your prepared PPT for a presentation at a meeting, which tablet is most helpful?
A. LeapPad Explorer 2. B. ipad 4th generation
C. Microsoft Surface D. Amazon Kindle Paperwhite.
C
Conventional wisdom says that hardship can make us old before our time. In fact, a new study suggests that violence not only leaves long?-term scars on children’s bodies, but also changes their DNA, causing changes that are equal to seven to ten years of premature aging.
Scientists measured this by studying the ends of children’s chromosomes(染色体), called telomeres, says Idan Shalev, lead author of a study published in Molecular Psychiatry.
Telomeres are special DNA sequences which prevent the DNA in chromosomes from separating. They get shorter each time a cell divides, until a cell cannot divide any more and dies.
Several factors have been found to shorten telomeres, including smoking, radiation and psychological stresses such as being treated badly when young and taking care of a chronically ill person.
In this study, researchers examined whether exposure to violence could make childre’s telomeres shorten faster than normal. They interviewed the mothers of 236 children at ages 5, 7 and 10, asking whether the youngsters had been exposed to domestic violence between the mother and her partner; physical maltreatment by an adult; or bullying. Researchers measured the children’s telomeres—in cells obtained by swabbing the insides of their cheeks—at ages 5 and 10.
Telomeres shortened faster in kids exposed to two or more types of violence, says Shalev. Unless that pattern changes, the study suggests, these kids could be expected to develop diseases of aging, such as heart attacks or memory loss, seven to 10 years earlier than their peers.
Shalev says there is hope for these kids. His study found that, in rare cases, telomeres can lengthen. Better nutrition, exercise and stress reduction are three things that may be able to lengthen telomeres, he says.
He study confirms a small ?but? growing number of studies suggesting that early childhood adversity imprints itself in our chromosomes, says Charles Nelson, a professor of pediatrics and neuroscience at Harvard Medical School.
74. The new study found that ________.
A. violence leaves scars on a child’s mind
B. hardship can change a child’s aging
C. violence can speed up a child’s aging
D. hardship has a long?-term effect on a child’s mind
75. According to the text, telomeres ________.
A. can make a cell die quickly
B. can help prevent DNA from separating
C. become shorter before they die
D. are at the ends of people’s chromosomes
76. All of the following things can shorten telomeres EXCEPT ________.
A. smoking B. cell division
C. maltreatment D. doing exercise
77. Which of the following is TRUE, according to the text?
A. Violence can cause quick cell division in children’s body.
B. Being treated badly will make a child’s telomeres shorten faster.
C. Researchers measured the children’s telomeres from their legs in the study.
D. Children who have shorter telomeres may have a heart attack earlier.
