Scientists in Israel have discovered a new way to test for water pollution by “listening” to what the plants growing in water have to say.
By shining a laser beam (激光束) on the tiny pieces of algae floating in the water，the researchers said they hear sound waves that tell them the type and amount of contamination (致污物) in the water.
“It is a red light，telling us that something is beginning to go wrong with the quality of water，” said Zvy Dubinsky，an aquatic biologist at Israel’s Bar Ilan University.“Algae is the first thing to be affected by a change in water quality.”“The secret，” he said，“is to measure the rate of photosynthesis (光合作用) in the algae，meaning the plant’s ability to transform light into energy.” During photosynthesis，plants also release oxygen into the air.
Dubinsky’s technique is easy to perform because of the overabundance of algae in the planet’s water.Most of the oxygen in the atmosphere comes from algae.A prototype tester that occupies about one square meter of a laboratory desktop，shoots a laser beam at water samples to stimulate photosynthesis in the algae.But not all of the laser’s heat is used.Depending on the condition of the algae and the rate of photosynthesis，some of the heat is shot back into the water，creating sound waves，Dubinsky said.With a special underwater microphone，researchers are able to analyze the strength of the sound waves and determine the health of the algae and the condition of the surrounding water.
“Algae suffering from lead poisoning，like waste discharged from battery and paint manufacturing plants，will produce a different sound than those suffering from lack of iron or exposure to other toxins，” said researcher Yulia Pinchasov.She said that testing algae photosynthesis can determine water quality more accurately and easily than laborintensive methods now used like chemical and radioactive carbon testing.The underlined word “algae” in Paragraph 2 probably refers to a kind of________.
| A．instrument | B．plant |
| C．wood | D．pollutant |
Why is the algae tested?
| A．Because it floats on the water. |
| B．Because it can have photosynthesis. |
| C．Because it is the first to be polluted. |
| D．Because it can produce different sounds. |
We can infer from the passage that________.
| A．algae can produce a loud sound when polluted |
| B．algae can die easily from pollution |
| C．photosynthesis of the algae can only be caused by sunlight |
| D．photosynthesis of the algae is related to water quality |
What would be the best title for the passage?
| A．Scientists Listen to Plants to Find Water Pollution |
| B．A Prototype Tester Is Used to Determine Water Pollution |
| C．The Importance of Photosynthesis of the Algae |
| D．The Problem of Chemical and Radioactive Carbon Testing |
My 18-month-old son, Adam, called from the front door．“Look, Mama! Doggie!” I dropped what I was doing and stuck my head out the door．Brandy, our next-door neighbor’s 11-year-old dog, was over again．“Go away!” I shouted．
Brandy’s owner had died about a month earlier．The woman’s family had emptied the house and stuck a “For Sale” sign in the front yard, but the family had left old Brandy behind．For weeks, she’d been wandering around the neighborhood．
It wasn’t that I disliked dogs or anything like that．I just didn’t think about them very much．I never had a dog growing up and had never thought to get one．
Brandy went away and I stayed outside with Adam．Then the phone rang．I went inside to take the call．When I came back, Adam was gone．I searched the yard, front and back, then the basketball court and public pool．No trace of him．I was so nervous that I ran home and called the police, then my husband．
Police searched the neighborhood．Suddenly I heard another sound: a dog barking．“It’s coming from the woods,” one of my neighbors said．We followed the barking to a wooded cliff（悬崖）．There we found my son, and he was just inches away from the edges of the cliff, fast asleep．Brandy was beside him, leaning（倚靠）against him to keep him away from the edge．When I picked Adam up, Brandy sank down on her side, breathing quickly．She must have been holding Adam there for hours!
I thanked the police and brought Adam and Brandy back to our house．She hesitated a moment on our doorstep, no doubt remembering the time I’d driven her away．
“Come on, girl,” I said．“This is your home now．” Brandy stepped in, and once she saw she was really welcome, she relaxed and lay down on the floor just inside the door．She’d done a great thing, and I wondered if she knew it ．She’d certainly touched me in a way that no animal ever had．What a pity a dog like Brandy had been left behind!What is the correct order for the events in the story about Brandy?
a．She was left behind by her owner’s family．
b．She stepped into the woman’s house．
c．She appeared at the woman’s front door．
d．She stayed beside the woman’s son for hours．
| A．d, a, b, c | B．a, c, b, d |
| C．c, d, b, a | D．a, c, d, b |
What did the woman do when she first saw Brandy?
| A．She gave her some food． |
| B．She drove her away． |
| C．She took her home． |
| D．She said thank you to her． |
How were they able to be aware that the woman’s son was near the cliff?
| A．By searching the neighborhood． |
| B．By hearing a dog barking． |
| C．By following a dog’s footsteps． |
| D．By hearing her son’s crying． |
If you need glasses to read this, you are among the majority of Chinese students. That’s because most students in China are short-sighted which means they can only see things close up and distant things will be blurry. Four-fifths of high school students wear glasses and now more and more children in primary school need glasses, too.
This epidemic of poor eyesight has two very simple causes: too much time spent indoors studying and too little time spent outdoors playing. Reading and writing for hours and hours, sometimes in poorly lighted rooms, causes eyesight to weaken. But students have to do this because there is so much pressure on them to succeed in school. And because they spend so much time indoors at school and at home, they have less time to spend outdoors enjoying the sun.
The sun, as a consequence, is important in developing good eyesight. Exposure to daylight releases a chemical in the eyes that prevents, or at least delays, short-sightedness. According to a study by Ian Morgan of Australian National University, Australian children and Chinese children have the same level of eyesight before they start school, but once they enter primary school, Chinese children only spend about an hour a day outside, while Australian children spend three to four hours each day in the sunshine. The result is that while about 40 percent of Chinese primary school students need glasses, only three percent of Australian children do.
Wearing glasses may not seem like a big deal. For some, wearing glasses can even be an opportunity to make a fashion statement. But poor eyesight at a young age can have serious long term consequences. As you get older, your eyesight can worsen and lead to things like macular degeneration(黄斑变性), a condition of the eyes for which there is no cure and which can eventually lead to blindness.
With all that in mind, don’t you think it’s time to give your eyes a break? Try spending a little less time inside and go for a walk in the park, instead. It’s the healthy thing to do and your eyes will thank you for it.What does the underlined word “blurry” mean?
| A．unpopular. | B．unpleasant. |
| C．unclear. | D．unconscious. |
How should the students protect their eyesight according to the passage?
| A．They should study less and less. |
| B．They should stay longer outdoors. |
| C．They should wear sun-glasses. |
| D．They should have a longer rest in bed. |
It can be inferred from the passage that _____ is to blame for the poor eyesight of Chinese children.
| A．the ever-worsening bad weather |
| B．the ever-increasing burden of study |
| C．the ever-decreasing sunny days |
| D．the ever-decreasing period of study time |
What is the purpose of this article?
| A．To explain why Chinese students are poor-sighted. |
| B．To admire Australian children’s good eyesight. |
| C．To criticize the present education system. |
| D．To call on people to protect Chinese children’s eyesight |
If you have a chance to go to Finland, you will probably be surprised to find how “foolish” the Finnish people are.
Take the taxi drivers for example. Taxis in Finland are mostly high-class Benz with a fare of two US dollars a kilometer. You can go anywhere in one, tell the driver to drop you at any place, say that you have some business to attend to, and then walk off without paying your fare. The driver would not show the least sign of anxiety.
The dining rooms in all big hotels not only serve their guests, but also serve outside diners. Hotel guests have their meals free, so they naturally go to the free dining rooms to have their meals. The most they would do to show their good faith is to wave their registration card to the waiter. With such a loose check, you can easily use any old registration card to take a couple of friends to dine free of charge.
The Finnish workers are paid by the hour. They are very much on their own as soon as they have agreed with the boss on the rate(价钱). From then on, they just say how many hours they have worked and they will be paid accordingly(相应地).
With so many loopholes(漏洞) in everyday life, surely Finland must be a heaven to those who love to take “petty advantages”. But the strange thing is, all the taxi passengers would always come back to pay their fare after they have attended to their business; not a single outsider has ever been found in the free hotel dining rooms. And workers always give an honest account of the exact hours they put in. As the Finns always act on good faith in everything they do, living in such a society has turned everyone into a real “gentleman”.
In a society of such high moral practice, what need is there for people to be on guard against others?While taking a taxi in Finland, ________.
| A．a passenger can go anywhere without having to pay the driver |
| B．a passenger pays two US dollars for a taxi ride |
| C．a passenger can never be turned down by the taxi driver wherever he wants to go |
| D．a passenger needs to provide good faith demonstration(证明) before leaving without paying |
We know from the passage that big hotels in Finland ________.
| A．are mostly poorly managed |
| B．provide meals for any diners |
| C．provide free wine and charge for food |
| D．provide meal for only those who live in the hotels |
Which of the following is NOT true according to the passage?
| A．The workers in Finland are paid by the hour. |
| B．The workers are always honest with their working hours. |
| C．The workers and their bosses will make an agreement in advance about the pay. |
| D．The bosses in Finland are too busy to check the working hours of their employees. |
The word “those” in the last but one paragraph probably refers to _______.
| A．people who are dishonest |
| B．people who often have meals in big hotels |
| C．people who often take taxis |
| D．people who are worthy of trust |
B
It is common and usual to see people freak out when they face challenges in their life. We all pass in different life problems and challenges. No one is free of life problems. Only a dead man faces no problem. As long as you are alive, challenges are everywhere.
How do you face problems and challenges in your life? Problems and challenges are the building blocks of your personality. They make you who you are. Besides, whether what happened in your life builds or destructs you depends on how you look at it. If you take your problems as troubles, they will be troubles and may cause destruction. If you take them as constructive tools, you are going to be built up on them.
Problems are everywhere. No one can avoid them. And they are good too. They open up a different look and opportunity if you are willing to see. When you face troubles, do not frustrate or freak out. Just cool yourself to think in a different direction. Think in a positive way. Every problem has its own good as well as bad sides. Focus on the good one. Look at the bright side.
Besides, there is always a good person, perhaps your mom or dad, or one of your friends, right beside you, who can turn everything into your best if you are willing to turn to them. No matter what happens, they will be there to help you. Trust them and they will never let you down. All you need to know is that you are loved wherever you are.What’s the meaning of the underlined phrase “freak out” in Paragraph 1?
| A．feel shy. | B．stay calm. |
| C．keep silent. | D．feel upset. |
In Paragraph 2, the writer implies(暗指) that ______.
| A．problems cause troubles |
| B．attitude is everything |
| C．challenges can be avoided |
| D．personalities are built on failures |
What’s the writer’s purpose to write the passage?
| A．To encourage. | B．To compare. |
| C．To prove. | D．To explain. |
What can be the best title of the passage?
| A．How to Avoid Problems |
| B．Challenges Are Everywhere |
| C．Face Your Challenges Bravely |
| D．You Are Loved Wherever You Are |
It was the end of my junior year, the weekend before prom (毕业舞会). I was riding with some friends, and a bottle was passed around the car. Everyone was taking swigs(一大口). When the bottle got to me, I thought:“What should I do?”I took a swig. It was the biggest mistake of my life. I had to drive home later that night.
I went back to my car, got in and drove off. At a stop sign I saw a policeman sitting in the parking lot across the street. His headlights were turned on, and I knew he was going to follow me. Then he flashed his lights at me. All I could think was: “Oh no, that swig!”
I pulled over and waited for him to come to my door. It felt like forever. “Can I see your license and registration, please, Miss?” I gave them to him. He took them and went back to his car for a while. When he returned, he asked if I had been drinking.
“No,” I said. He asked me to step out of my car.
“Walk heel to toe down the white line, please.” I passed the test. Next he had me stand on my left foot, lift my right foot and hold it for 30 seconds. I’m not the most coordinated (动作协调的) person and I can’t even walk and chew gum at the same time, so, needless to say, I didn’t pass. Then he asked me to take a breathalyzer test.
That was where I messed up. I told him I didn’t want to and didn’t understand why I had to. The officer asked me three more times, and I continued to refuse. He told me to turn around and place my hands behind my back. He arrested me right then and there.
The policeman drove me to a police station 20 minutes from my home. He called my parents and told them where I was.
I went to court two months after that, charged with refusing to obey an officer. I got a $700 (4,340 yuan) fine and 40 hours of community service. I’ll be on probation (缓刑) for a year, and I’ll have to take the driving test again. I lost my license for a whole year.
This was a huge learning experience for me. It opened my eyes to how easy it is to make a stupid decision. I want everyone reading this to know that it’s not right to drink and drive. It definitely isn’t worth losing your license over.From the first paragraph, we can conclude that the author __________.
| A．didn’t remember she had to drive home later when riding with her friends |
| B．wished she had refused to drink that night |
| C．felt just one mouthful would not affect her driving |
| D．lost her driving license on the way |
Which of the following is TRUE according to the article?
| A．The author was in jail for 40 hours and had to do community service. |
| B．The author thought her punishment shouldn’t be so serious. |
| C．The author was really sorry that she had made a serious mistake. |
| D．The author believed she would have avoided punishment if she had obeyed the policeman. |
What is the main purpose of the article?
| A．To warn people against driving after drinking. |
| B．To explain how policemen test drivers. |
| C．To show that severe punishment works. |
| D．To blame the author’s thoughtless friends. |
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