Your cellphone holds secrets about you. Besides the names and numbers that you’ve programmed into it, traces of your DNA remain on it, according to a new study.
DNA is genetic material that appears in every cell. Like your fingerprint, your DNA is unique to you-unless you have an identical twin. Scientists today usually analyze DNA in blood, saliva(唾液), or hair left behind at the scene of a crime. The results often help detectives identify criminals and victims.
Meghan J. McFadden, a biologist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cellphone and later dropped it. This made her wonder whether traces of DNA remained on cellphones-even when no blood was involved. To find out, she and a colleague collected flip-style(翻盖式) phones from 10 volunteers. They collected invisible traces of the users from two parts of the phone: the outside, where the user holds it, and the speaker, which is placed at the user’s ear.
The scientists cleaned the phones using a liquid mixture made mostly of alcohol. The aim of washing was to remove all delectable traces of DNA. The owners got their phones back for another week. Then they returned the phones and the researchers collected traces on each phone once more. They discovered DNA that belonged to the phone’s owner on each of the phones.
Surprisingly, DNA was even picked up immediately after the phones were cleaned. That suggests that washing won’t remove all traces of evidence from a criminal’s cellphone. So cellphones can be added to the list of clue the can settle a crime-scene investigation.
68. What’s the main idea of the passage?
A. The cellphone means most secrets of its owner.
B. McFadden is famous for her secrets of its owner.
C. The investigation of a crime is a hard job.
D. DNA can be available on the user’s cellphone.
69. In a crime-scene investigation, now experts are likely to turn to .
A. the criminal’s fingerprint B. the DNA analysis of physical items
C. the detectives D. the criminal’s cellphone
70. According to the passage, McFadden was inspired by .
A. the secrets stored in people’s cellphones B. the special characters of DNA
C. a cellphone-involved case D. the challenging job of detectives
71. According to the passage, the potential application of the new study would be .
A. identifying criminals B. designing new cellphones
C. protecting individual privacy D. preventing cellphone-involved crime
The future of pinnipeds (鳍足动物)looks much brighter today than it once did. At one time, about 100 years ago, it seemed certain that many pinnipeds in the world would be destroyed by human hunters. Today, it appears that most species( 物种) of pinnipeds are out of danger.
Hunting was not controlled during the 18th and 19th centuries, because little was known about the lives of pinnipeds. Whales and pinnipeds were hunted for the oil from their body fat. This oil was used in lamps before electric lights were invented. Millions of seals and other pinnipeds were used to provide oil for the lamps of the world. As a result, the numbers of many pinniped species fell rapidly.
Several things happened that helped to save pinnipeds. First, species that were hunted to near extinction (灭绝) were left alone because their numbers were too low and the cost of hunting them went up greatly. At the same time, electric lights were invented and the market for seal oil became smaller. Finally, governments around the world made laws to protect pinnipeds.
As a result of all these things, the numbers of most pinniped species have grown in recent years. With some species, such as Northern fur seals, there may be as many animals alive today as there were before all the hunting began.
However, oil is still a danger to pinnipeds and all sea animals. But this time it’s not because they are hunted for their oil. The oil that puts them in danger is from oil spills(泄露) in the sea. The oil covers their fur and reduces their body temperatures. Oil also sticks to the foods they eat. This modern danger to pinnipeds and their environment is one we must work to prevent. During the 18th and 19th century, _______.
| A．people had realized the importance of pinnipeds |
| B．pinnipeds were hunted for their meat |
| C．pinnipeds had a better life than today |
| D．many families were using lamps |
What does Paragraph 3 mainly talk about?
| A．How electric lights were invented. |
| B．When people began to protect pinnipeds. |
| C．What governments around the world have done to save pinnipeds. |
| D．Why the numbers of some pinnipeds have increased. |
It can be inferred from the passage that________.
| A．the market for seal oil is growing |
| B．Northern fur seals aren’t in much danger now |
| C．oil spills are the biggest problem for pinnipeds |
| D．stricter laws need to be made to protect pinnipeds |
In which part of a magazine can we most probably read this passage?
| A．Wildlife. | B．Lifestyle. |
| C．Tourism. | D．Environment. |
The associates I hired in my bicycle and lawn mower shop like myself were never perfect; however, they were excellent. Working with them as they improved taught me new ways to show forgiveness, understanding, and patience.
One day the placement officer asked me to interview a young man who was having trouble finding a job. He told me that David was a little shy, did not talk much and was afraid to go on with interviews. He requested that I give David an interview just for practice. He plainly told David that I had no positions open at the time and the interview was just for practice.
When David came in for the interview, he hardly said a word. I told him what we did at the bicycle shop and showed him around. I told David to keep showing up because the number one thing an employer wanted in an associate was dependability.
David was very quiet ( he was evaluated as a slow learner in school). Every ten days or so, for weeks after the interview, David walked into the bicycle shop and stood by the front door. He never said a word, just stood by the door.
One day, shortly before Christmas, a large truck came to the shop, packed with 250 new bicycles. It had to be unloaded right away or the driver would leave.
It was raining. Some of my workers (without physical limitations) chose not to brave the weather to get into work, so I was short-handed. It seemed everything was going wrong and on top of it, David came in the front door and just stood there. I looked at him and shouted, “Well, all right! Fill out a time card and help me unload this truck!”
David worked for my bicycle shop for eighteen years. He came to work every day thirty minutes early. He could talk; however, he rarely chose to. He drove my truck and made deliveries. The customers would praise David, saying, “He doesn’t talk, but he really shows you how to operate a lawn mower!”The author gave David an interview to _______
| A．find a person who is reliable |
| B．find a part-time worker in need |
| C．give him some practice |
| D．show sympathy for him |
The author finally hired David because________
| A．there were no other workers in the shop then |
| B．he needed someone who was willing to work then |
| C．David kept showing up |
| D．He realized David was dependable |
We can infer from the last paragraph that_______
| A．some customers just play jokes on David |
| B．David has had his character changed through work |
| C．the author prefers David to be more outgoing |
| D．the author feels lucky to hire David |
For about three years now, I have been writing poetry. It was not until my junior year in high school that I developed an interest, love, and skill for writing poetry.
Back in elementary school, I love to write stories. I would write stories on post-it notes and anywhere I could. Yet when I had to write a limerick （五行打油诗）for an assignment, I could not wrap my head around poetry. I had a very hard time figuring out how to rhyme words and have the words make sense. I eventually tossed the paper with the attempted limerick in the trash. I did not try my hand at poetry again until several years later.
Many years later in my freshman year of high school, my English teacher gave my class a poetry project as an assignment. I still remember my limerick assignment and was afraid of doing the poetry. For the project, we had to analyze a poem and write a response to it. I choose to respond to Robert Frost’s poem Fire and Ice. I also wrote my own poem first. I become really excited when writing the poem.
Two years later, I started writing poetry, as a hobby and for fun. To learn how good or bad my poems were, I handed them in to some magazines and contests. I won second place in the North Carolina Poetry Society’s Sherry Pruitt Award Contest with a poem called The Ocean, and had my two poems published as high merit (优等) poems. I have continued to write poetry, and have even self-published three collections of poetry in both print and e-book formats, which can be found at my store on Lulu.
Now, I love writing poetry, but I don’t hate writing short stories. I just find it more difficult and not my style of writing, even though I still write short stories occasionally.When the author was a pupil, he ____.
| A．liked writing stories |
| B．was good at writing poetry |
| C．could understand poetry well |
| D．was often praised by his teacher |
When given the poetry project in high school, the author was ______.
| A．excited | B．annoyed |
| C．confident | D．worried |
The author took up writing poetry as a hobby when he ____.
| A．was in Grade Three in high school |
| B．worked as a storekeeper |
| C．was in Grade One in high school |
| D．was at college |
How did the author increase his confidence in writing poetry?
| A．He wrote a lot of poems and asked advice from his teacher |
| B．He published three collections of poetry by himself |
| C．He submitted his poems to magazines contests |
| D．He gave up writing stories and only wrote poetry |
Ereading and ebooks are slowly conquering the world.Compared to traditional paper books，ebooks in some schools and universities attract more interest because the information flow seems much easier to manage and comes in a greatly higher quantity.
Japan is known for the reformminded attitude towards the gadget(精巧装置) world and for the fact that it is one of the first countries that encouraged in the educational system the emailing of homework.
The digital textbook looks like the logical step in the world of learning.It is natural but it is also completely untraditional.
The plan of the largest publishing companies to get in line with the trend is to save a large quantity of paper and make the kids become interested in learning using a cool gadget.Many USA universities and colleges have made students be used to the procedure of downloading the courses and of course the procedure involves interactive software and also the chance of using the computer.
The traditional education system is still unwilling when it comes to giving up books.The standard approach of information taught out of a book and Shakespeare read out of an old school novel makes studying English as traditional as it can be.
In a world where kids would rather see the movie than read a book，the digital age has brought along a completely different flavor to reading.Bringing that flavor in school will make teaching a greener and also a completely different matter.Why are ebooks so popular in the world?
| A．It's cheap to buy. |
| B．It's effective to use. |
| C．It's convenient to bring. |
| D．It's the latest fashion. |
Which of the following words can best take the place of the word “reformminded” in the second paragraph?
| A．Oldfashioned. | B．Aggressive. |
| C．Rejecting. | D．Progressive. |
In America，the students are encouraged to________．
| A．apply the procedure of downloading the courses |
| B．communicate with their teachers using computer |
| C．research some interactive software for their studies |
| D．do their homework in computer instead of in paper |
What's the author's attitude to the digital textbooks?
| A．Being against. | B．Being for. |
| C．Not mentioned. | D．Being neutral. |
Tom appeared on the sidewalk with a bucket of whitewash and a long-handled brush. He stopped by the fence in front of the house where he lived with his aunt Polly. He looked at it, and all joy left him. The fence was long and high. He put the brush into the whitewash and moved it along the top of the fence. He repeated the operation. He felt he could not continue and sat down.
He knew that his friends would arrive soon with all kinds of interesting plans for the day. They would walk past him and laugh. They would make jokes about his having to work on a beautiful summer Saturday. The thought burned him like fire.
He put his hand into his pockets and took out all that he owned. Perhaps he could find something to pay someone to do the whitewashing for him. But there was nothing of value in his pockets. So he put the bits of toys back into his pockets and gave up the idea.
At this dark and hopeless moment, a wonderful idea came to him. It filled his mind with a great, bright light. Calmly he picked up the brush and started again to whitewash.
While Tom was working, Ben Rogers appeared. Ben was eating an apple as he walked along the street. When he came close to Tom, he stopped.
Tom went on whitewashing. He did not look at Ben. Ben stared a moment and then said: “Hello! I’m going swimming, but you can’t go, can you?”
No answer. Tom moved his brush carefully along the fence and looked at the result with the eye of an artist. Ben came nearer. Tom’s mouth watered for the apple, but he kept on working.
Ben said, “Hello, old fellow, you’ve got to work, hey?”
Tom turned suddenly and said, “Why, it’s you, Ben! I wasn’t noticing.”
“I’m going swimming. Don’t you wish you could? But of course you’d rather work. You seem to like it very much.”
“Like it? Well, I don’t see why I shouldn’t like it. Does a boy get a chance to whitewash a fence every day?”
Ben stopped eating his apple. Tom moved his brush back and forth, stepped back to look at the result, added a touch here and there, and stepped back again. Ben watched every move and got more and more interested. Soon he said,
“Tom, let me whitewash a little.”
Tom thought for a moment, was about to agree; but he changed his mind.
“No, no, it won’t do, Ben. You see, Aunt Polly wants this fence to be perfect. It has got to be done very carefully. I don’t think there is one boy in a thousand, maybe two thousand, that can do it well enough.”
“No — is that so? Oh come, let me just try. Only just a little.”
“Ben, I’d like to, but if it isn’t done right, I’m afraid Aunt Polly ...”
“Oh, I’ll be careful. Now let me try. I’ll give you half of my apple.”
“Well, here — No, Ben, now don’t. I’m afraid ...”
“I’ll give you all of it.”
Tom gave up the brush with unwillingness on his face, but joy in his heart. And while Ben worked at the fence in the hot sun, Tom sat under a tree, eating the apple, and planning how to get more help. There were enough boys. Each one came to laugh, but remained to whitewash. And when the middle of the afternoon came, Tom had won many treasures. The fence had been whitewashed three times. If he hadn’t run out of whitewash, Tom would have owned everything belonging to his friends.
He had discovered a great law of human action that in order to make a man or a boy want a thing, it is only necessary to make the thing difficult to get.Why did Tom take all his bits of toys out of his pockets?
| A．Because he was tired and wanted to play with his toys. |
| B．Because he wanted to exchange his toys with his friends. |
| C．Because he wanted to give his toys to his friends. |
| D．Because he wanted to know if he could buy help with his toys. |
Tom was about to agree to let Ben whitewash when he changed his mind because ______.
| A．Tom wanted to do the whitewashing himself |
| B．Tom planned to make Ben give up his apple first |
| C．Tom was unwilling to let Ben do the whitewashing |
| D．Tom was afraid Ben couldn’t do the whitewashing well. |
We can learn from the passage that ______.
| A．Tom was fond of whitewashing the fence |
| B．Tom had a lot of friends who were ready to help him |
| C．Tom managed to let other boys do the whitewashing for him |
| D．Tom was better at whitewashing the fence than others |
Which of the following is the most suitable title for this passage?
| A．The Happy Whitewasher |
| B．Tom And His Fellows |
| C．Whitewashing A Fence |
| D．How To Make Things Difficult To Get |
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