One Monday morning, Paul and his classmates were in science laboratory for their

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One Monday morning, Paul and his classmates were in science laboratory for their

题型：不详难度：来源：
One Monday morning, Paul and his classmates were in science laboratory for their practical chemistry lesson. The students were going to work in pairs to do an experiment. Before they began, the teacher gave them this description of the different stages of the experiment.
Stage 1: Prepare the equipment: a test tube, a crucible, a Bunsen burner and tongs.
Stage 2: Weigh 5 grams of baking soda (sodium bicarbonate) and put it in a crucible.
Stage 3: Heat 10 ml of hydrochloric acid (盐酸) in a test tube.
Stage 4: Pour the warm acid onto the baking soda and continue to heat the mixture.
Result: The acid reacts with the bicarbonate（碳酸氢盐）to form water, carbon dioxide gas and salt. The hotter the mixture, the quicker the reaction. Continue to heat the mixture until the water evaporates, leaving the salt in the crucible.
Paul and his partner followed the instructions and set up their equipment. Paul went to the cupboard to get a bottle of hydrochloric acid. He found that there was only one bottle in the cupboard so he took that. There was no label on the bottle and Paul didn’t check with the teacher if it was the right solution.
He measured the liquid and poured it into a test tube. Using tongs to hold the test tube, he heated it over the Bunsen burner. That’s when things started to go wrong. The liquid in the test tube was not hydrochloric acid. When it was heated, it formed a thick cloud of white gas. Soon the room was full of this strong smelling white gas.
All the students started coughing and their eyes hurt. The teacher immediately opened the windows and ordered the students to leave the laboratory at once. She realized that the liquid was a crylamide (丙烯酰胺) and that it is poisonous.
Fortunately, nobody was injured in the incident. However, it taught the students and the teacher a good lesson.
小题1:What lesson did the incident teach the students and the teacher?
A．Never have a bottle without a label in the chemistry lab!
B．Obey your teacher’s instructions in the Chemistry lab.
C．A crylamide can’t take the place of hydrochloric acid.
D．Finding something unusual happened, you have to leave the laboratory at once.
小题2:What substance were the students making in the experiment?
A．WaterB．Carbon dioxide gasC．SaltD．Poisonous gas
小题3:Why did Paul make the mistake?
A．He went to the cupboard to get the bottle by himself.
B．He found that there was only one bottle in the cupboard so he took that.
C．There was no label on the bottle.
D．Paul didn’t check with the teacher that it was the right solution.
小题4:Why did the teacher send the students out of the classroom?
A．Becausethe room was full of this strong smelling white gas.
B．Because all the students started coughing and their eyes hurt.
C．Becausethe liquid was a crylamide and that it is poisonous.
D．Because someone was injured in the incident.

答案

小题1:A
小题2:C
小题3:D
小题4:C
解析

试题分析：一天上午，Paul和同学们在科学实验室上化学实验课。同学们在老师的指导下分组进行实验。Paul误用了一个没有贴标签瓶子里的液体，结果出现了意外，丙烯酰胺反应后生成了有毒的气体。
小题1:根据文章可知，同学们遵守老师的指导进行实验，排除B；Paul不知道瓶子里装的是crylamide，排除C；出现紧急情况时，要看情况的严重性再作出判断，排除D。实验出错的原因是Paul用了那个没有贴标签的瓶子里面的物质，故选A。
小题2:根据“The acid reacts with the bicarbonate（碳酸氢盐）to form water, carbon dioxide gas and salt. ...leaving the salt in the crucible”可知，同学们做实验要得到的物质是盐，故选C。
小题3:根据“there was only one bottle in the cupboard so he took that. There was no label on the bottle and Paul didn’t check with the teacher if it was the right solution”可知，瓶子上没有贴标签，Paul没有和老师一起检查这个瓶子是否适合做实验用，故选D。
小题4:根据“She realized that the liquid was a crylamide (丙烯酰胺) and that it is poisonous.”可知，老师发现发生反应的是丙烯酰胺，而丙烯酰胺是有毒的，故选C。
举一反三


techniques , but he admitted there would be difficulties in meeting his goal .
“ For example , if you run out of ink while printing on paper , you will throw that paper away . But you cannot throw half-completed buildings away if your material gets stuck , ” he said . Although the printed house is not available to visit , there is a chance for people in Shanghai to see items printed in 3D.
The Belgium-based company Materialise NV held a 3D printing exhibition in Shanghai that started in late 2012 and ended in the middle of 2013 . The company is eager to show Asia what is possible with 3D printing .
“ All the pieces shown here are what cannot be made through traditional techniques . A good example of this customization is hearing aids . More than 10 million people already use 3D printed hearing aids, all made according to the size of their ears , ” said Wim Michiels , executive vice-president at Materialise NV .
“ You can produce anything whenever and wherever you like . You don’t need to set up production lines for pieces that only need a limited amount of products . Setting up a production line is a lot of work . It takes a long time and is very expensive for a limited number of pieces , ” said Michiels .
Kim Francois , managing director of Materialise China , said their European and American clients have already taken the next step toward additive manufacturing with small series production such as hearing aids .
小题1:What is mainly talked about in the text ?
A. The development of 3D printing .
B. A 3D printing show in Shanghai .
C. Varieties of items printed in 3D .
D. The company Materialise NV .
小题2:According to Behrokh Khoshnevis , what is the main difficulty in printing buildings ?
A．Time .B．Technique .C．Space .D．Material .
小题3:The example of 3D printed hearing aids was mentioned to show that ______________ .
A．these items used to be impossible to make
B．3D printing has a large market share
C．3D hearing aids help people hear better
D．people need different sized hearing aids
小题4:According to the text , 3D printing is suitable for ___________ .
A．mass production
B．making small items
C．small series production
D．reducing production costs

题型：不详难度：| 查看答案
So long as teachers fail to distinguish between teaching and learning, they will continue to undertake to do for children that which only children can do for themselves. Teaching children to read is not passing reading on to them. It is certainly not endless hours spent in activities about reading. Douglas insists that “reading cannot be taught directly and schools should stop trying to do the impossible”.
Teaching and learning are two entirely different processes. They differ in kind and function. The function of teaching is to create the conditions and the climate that will make it possible for children to devise the most efficient system for teaching themselves to read. Teaching is also public activity. It can be seen and observed.
Learning to read involves all that each individual does to make sense of the world of printed language. Almost all of it is private, for learning is an occupation of the mind, and that process is not open to public scrutiny.
If teacher and learner roles are not interchangeable, what then can be done through teaching that will aid the child in the quest（探索）for knowledge? Smith has one principal rule for all teaching instructions. “Make learning to read easy, which means making reading a meaningful, enjoyable and frequent experience for children.”
When the roles of teacher and learner are seen for what they are, and when both teacher fulfill them appropriately, then much of the pressure and feeling of failure for both is eliminated. Learning to read is made easier when teachers create an environment where children are given the opportunity to solve the problem of leaning to read by reading.
小题1:The problem with the reading course as mentioned in the first paragraph is that ________.
A．it is one of the most difficult school courses
B．students spend endless hours in reading
C．reading tasks are assigned with little guidance
D．too much time is spent in teaching about reading
小题2:The teaching of reading will be successful if ________.
A．teachers can improve conditions at school for the students
B．teachers can enable students to develop their own way of reading
C．teachers can devise the most efficient system for reading
D．teachers can make their teaching activities observable
小题3:The underlined word“ scrutiny” most probably means“________”.
A．inquiryB．observationC．controlD．suspicion
小题4:According to the passage, learning to read will no longer be a difficult task when ________.
A．children become highly motivated
B．teacher and learner roles are interchangeable
C．teaching helps children in the search for knowledge
D．reading enriches children’s experience
小题5:The main idea of the passage is that ________.
A．teachers should do as little as possible in helping students learn to read
B．teachers should encourage students to read as widely as possible
C．reading ability is something acquired rather than taught
D．reading is more complicated that generally believed

题型：不详难度：| 查看答案
Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It’s more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone’s origin.
Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year’s meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone’s homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.
Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.
To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.
The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements（元素）produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.
In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.
Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.
小题1:We learn from Paragraph 1 that __________________.
A．an emerald and a ruby are names of diamonds.
B．it’s not difficult to tell where the gem was mined.
C．appearances help to identify the origin of gemstones.
D．diamonds from different places may appear the same.
小题2:Why did the U.S. government pass law that requires companies selling gemstones to determine the origins of their stones?
A．To look for more gemstones.
B．To encourage violent civil wars.
C．To reduce the trade in blood minerals.
D．To develop the economy.
小题3:Which of the following facts most probably helps McManus and her team in identifying the origin of stones?
A．Heat can turn ice into water or water into steam.
B．Gemstones from the same area produce similar light patterns.
C．Laser can changes a miniscule part of the gemstone into plasma.
D．Materialytics has already collected patterns from thousands of gemstones.
小题4:From the last two paragraphs, what can be inferred about the laser technique?
A．It is ready for commercial use.
B．People can use the new tool to find more gemstones.
C．It can significantly reduce the gemstones trade in blood minerals.
D．It will bring about a revolutionary change in identifying the origin of minerals.
小题5:The author wrote this passage mainly to ________.
A．tell us how to identify the origin of diamonds.
B．introduce a laser technique in identifying a stone’s origin
C．prove identifying the origin of gemstones are difficult
D．attract our attention to reducing trade in blood minerals

题型：不详难度：| 查看答案
Barack Obama, Lady Gaga and Steve Jobs—what do they have in common? They are, of course, all Americans. And according to a survey by social networking site badoo. com, they all best illustrate(举例说明) the word “cool”.

But just what does it mean to say someone is “cool”? Most would answer that it is something to do with being independent-minded and not following the crowd.
Yale University art professor Robert Farris Thompson says that the term “cool” goes back to 15th century West African philosophy(哲学).  “Cool” relates to ideas of grace(优雅) under pressure.
“In Africa, ” he writes, “coolness is a positive quality which combines calmness, silence, and life.”
The modern idea of “cool” developed largely in the US in the period after World War II. “Post-war ‘cool’ was in part an expression of war-weariness (n. 厌战情绪)
. . . it went against the strict social rules of the time,” write sociologists Dick Pountain and David Robins in Cool Rules:Anatomy of an Attitude.
But it was the American actor James Dean who became the symbol for “cool” in the hugely successful 1955 movie Rebel without a Cause.  Dean plays a tough guy who disobeys his parents and the authorities. He always gets the girl, smokes cigarettes, wears a leather jacket and beats up bullies(欺凌弱小者). In the movie, Dean showed what “cool” would mean to American young people for the next 60 years.
Today the focus of “cool” has changed to athletics (体育运动) stars. Often in movies about schools, students gain popularity on the athletics field more than in the classroom. This can be seen quite clearly in movies like Varsity Blues and John Tucker Must Die.
But many teenagers also think being smart is cool. Chess and other thinking games have been becoming more popular in schools.
“Call it the Harry Potterization of America—a time when being smart is the new cool,” writes journalist Joe Sunnen.
小题1:Barack Obama, Lady Gaga and Steve Jobs are mentioned in the first paragraph to ________.
A．introduce the topicB．draw our attention
C．tell us what they have in commonD．tell us what is “cool”
小题2:If you were considered “cool” in Africa in the 15th century, you ________.
A．thought and acted differently from the majority
B．had a calm and quiet attitude towards life
C．didn’t observe rules and authorities
D．had all kinds of “bad” manners
小题3:The heroes in Varsity Blues and John Tucker Must Die are likely to be those who ________.
A．do very well in their studies
B．are very skilled at sports
C．are good at chess and other thinking games.
D．have supernatural powers like Harry Potter
小题4:Which of the following is NOT true according to the article?
A．It is generally considered “cool” to be independent-minded and not to follow the crowd.
B．“Cool” was used as early as the 15th century.
C．Disobeying one’s parents and the authorities is considered “cool” among American young people nowadays.
D．Getting the first place in an exam can also be considered “cool”.
小题5:What does the article mainly talk about?
A．The origin of the word “cool”.
B．The kinds of people who are “cool”.
C．The changing meaning of the word “cool”.
D．How to be a “ cool” person.

题型：不详难度：| 查看答案
Air pollution is one of the hottest topics at present because poor air quality is an important factor in both the incidence and cause of respiratory(呼吸道) diseases.
Zhong Nanshan, a deputy to the NPC and a member of the CAE, said recently when the concentration of PM2.5 rises by 10 micrograms per cubic meter, hospitalization may rise by as much as 3.1 percent. Meanwhile, when the concentration of PM2.5 rises from 25 mgs per cubic meter to 200, the average daily death rate may rise to 11 percent.
Zhi Xiuyi, a leading expert in lung cancer treatment and also vice-president of the CATS, said medical authorities used to focus on tobacco control as a primary means of preventing lung cancer. "But in fact, air pollution is no less harmful than smoking and our research team released a report earlier this year showing that the cancer rate in Beijing is closely related to industrialization," he said.
The report, conducted by the Beijing Institute of Cancer Research, shows that the number of cancer patients in China has increased markedly during the past ten years. Chaoyang District, the city"s main area of industrialization, has the highest incidence of cancer, almost double that of Yanqing, an area on the outskirts of the city. About four out of 1000 Chaoyang residents have some form of the disease, with lung cancer at the top of the list.
"The risk of having cancer largely depends on the length of exposure and the concentration of noxious gases(有毒气体的浓度)," said Zhi. In response to the doubt whether seven years" exposure to poor air quality will almost result in cancer, Zhi said the time scale was taken from research overseas that suggested the rate of incidence generally peaked in the seventh year of exposure to a heavily polluted environment.
小题1: What is the passage mainly about?
A．Medical researches on environment.
B．The disadvantages in big cities.
C．The only reason for the lung cancer.
D．Poor air quality contributing to lung cancer.
小题2:What can you conclude from the 3rd paragraph?
A．Compared with smoking, air pollution is more harmful.
B．Air pollution is as harmful as smoking.
C．It is very important to prevent people from smoking.
D．People realize the importance of keeping healthy.
小题3:If there were 3,000,000 people in Chaoyang District, how many would have respiratory diseases?
A．16000B．12000C．8000D．7500
小题4:What can you infer from the passage?
A．Industrialization has its weakness as well as strengths.
B．The average death rate rises with different ages and places.
C．The air in Beijing is much more polluted than that in the other cities.
D．The more heavily-polluted air you breathe in, the sooner you’ll have cancer.

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