A cellphone is one of the few things that we hold close to our faces all the time, and yet it could possibly explode - this is what made the recent Samsung’s Galaxy Note 7 smart-phone accidents so shocking.

According to technology news website The Verge, flawed（有瑕疵的）phone batteries might be to blame.

Even if you are not a science student, you probably know that it is common sense that the anode (the negative（負的）end of the battery) and the cathode (the positive end) should never touch. If they do, the battery will short-circuit（短路）, causing a powerful electrical reaction that can destroy the battery and cause a fire.

This is why all lithium-ion（鋰離子）batteries - the kind that can be found in many of our devices like tablets and cameras - have a separator layer inside to stop the two ends from touching one another.

But somehow, the separators in some of the Samsung phones broke, causing explosions.

Overcharging is another problem that can make batteries heat up quickly. Fortunately, most batteries are designed to be able to automatically stop charging once they are fully charged. But again, this somehow failed to happen in some of the Samsung phones.

The two “somehows” may sound random（隨機的）and hard to explain. But they actually both come from the fact that phone producers have been pushing the limits of batteries to meet customers’ demand for a longer battery life.

According to Lynden Archer, a materials scientist at Cornell University, US, we have already achieved 90 percent of the battery life possible from a lithium-ion battery. Customers’ demand that their devices get thinner has also given producers little choice but to try to put more power into thinner batteries.

“The more energy you put into a box, the more dangerous it’s going to be,” Billy Wu, a lecturer at Imperial College London, told The Guardian.

A thinner battery also means producers have to use thinner material for separators, and thinner material has more chance of breaking.

1.A separator layer is put in lithium-ion batteries in order to ___________.

A. ensure a longer battery life

B. prevent a battery from short circuiting

C. connect the anode and the cathode

D. reduce a certain electrical reaction

2.What are the direct reasons for the Samsung phone explosions?

A. Short circuiting and overheating

B. Pushing the limits of batteries

C. Overcharging and thinner batteries

D. Automatic charging and broken separators

3.Lynden Archer’s comments indicate that ___________.

A. demands for thinner cellphones are unreasonable

B. lithium-ion batteries can’t hold much more power than that they do now

C. producers can use 10 percent of a lithium-ion battery

D. new material for batteries is needed to meet consumers’ demands

4.What is the writer’s main purpose of writing the article?

A. To describe problems facing cellphone producers

B. To explain the reasons for the Samsung phone explosions

C. To teach us common sense when it comes to batteries

D. To warn us about the dangers of lithium-ion batteries

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科目：高中英語 來源：廣東省化州市2015-2016學(xué)年高一上學(xué)期期中考試英語試卷 題型：七選五

Ways to make a great first impression

You’ve heard it a million times already, but it really does take but a few seconds to make that all-important first impression (印象). Here are some easy ways for you to impress your classmates or teachers.

● 1.

Before you shake hands with somebody, make sure that your hands are clean. The handshake should not be too strong or weak. Most people use their right hands, unless they have a reason to use the left. 2.

● Be on time

When meeting someone for the first time, arriving on time is as important as breathing. You may have an excuse, but that will leave the person who hardly knows you with a bad impression. 3. It’s better to be hanging around the place than be stuck in traffic.

● Introduce yourself and ask for names

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G. It could be a similar taste in clothes or a common hobby.

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科目：高中英語 來源：河南省原名校（即豫南九校）2018屆高三第二次質(zhì)量考評英語試卷 題型：短文改錯

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Getting rid of the bad habit of procrastination(拖延癥)is now my goal in life. My first step was to set small targets what can be reached realistically. For example, I plan to set a timetable for my study. So after school, I will put finishing homework in the last place. Additionally, I will make a list of my important task including their due dates but follow my schedule strictly. I will avoid find excuses for putting them off. At same time, I will ask for my friends and parents to help me. By achieving this small targets, I have confident that I will overcome procrastination.

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科目：高中英語 來源：內(nèi)蒙古2017-2018學(xué)年高二上學(xué)期第一次月考英語試卷 題型：書面表達

假如你是李華。你的朋友Tommy是一個手機低頭族，無論站著、坐著、走著，他都在低頭玩手機。請就此給Tommy寫一封信，說服他改掉這個壞習(xí)慣。

注意：1．詞數(shù)100左右；

2．可適當增加細節(jié)，以使行文連貫；

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參考詞匯：過度使用overuse

Dear Tommy,

There are many people now playing with their cell phones no matter where they are. And I know you are not an exception.

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刪除：把多余的詞用斜線（\）劃掉。

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2. 只允許修改10處，多者（從第11處起），不計分.

When I was a child, I hoped to live in the city. I think I would be happy there. Now I am living in a city , but I miss my home in countryside. There the air is clean or the mountains are green. Unfortunately, on the development of industrialization, the environment has been polluted. Lots of studies have been shown that global warming has already become a very seriously problem. The airs we breathe in is getting dirtier and dirtier. Much rare animals are dying out . We must found ways to protect your environment. If we fail to do so , we’ll live to regret it .

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科目：高中英語 來源：內(nèi)蒙古2017-2018學(xué)年高二上學(xué)期第一次月考英語試卷 題型：閱讀理解

People tend to become more personal and hide less of themselves when using email. Researchers from Open University in Britain have found in a recent study that there are good reasons for this.

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Generally the information was not extremely personal. It was mainly about things such as where they went to school, or where they used to live. But some students discussed their love stories, and personal childhood experiences.

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1.The subject discussed in this passage is _______.

A. how people do research studies

B. how people open up when emailing

C. how to communicate at work

D. how to discuss and solve a problem

2.The reason that some couples talked freely about themselves is that _______.

A. they didn’t talk about very personal things

B. they couldn’t see each other

C. the cameras on the computers were turned on

D. they had to discuss a question

3.In the writer’s opinion, one should ______.

A. focus on oneself when emailing

B. talk more freely in emails than usual

C. consider how one uses email at work

D. discuss any subject that one wants to

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科目：高中英語 來源：河南省新鄉(xiāng)市2018屆高三（衛(wèi)星班）上學(xué)期第一次月考英語試卷 題型：閱讀理解

Many foreign students report feeling lonely or unwelcome in Australia. Those feelings are among the reasons why Australia is taking a close look at its international education industry. But wherever international students go, making friends may not always be easy. Elisabeth Gareis of Baruch College in New York surveyed 454 international students. They were attending four-year colleges and graduate schools in the American South and Northeast.

Students from English-speaking countries and from northern and central Europe were more likely to be happy with their friendships. But 38% of the international students said they had no close friends in the United States. And half of the students from East Asia said they were unhappy with the number of American friends they had. Thirty percent said they wished their friendships could be deeper and more meaningful.

Professor Gareis says, “Students from East Asia have cultures that are different on many levels from the culture in the United States. There are also language problems, and maybe some social skills, such as small talk, which are possibly not as important in their native countries, where it's not as important to start friendships with small talks. Many East Asian students blamed themselves for their limited friendships with Americans, for not speaking the language well enough and for not knowing the culture well enough.

VOA's Student Union blogger Jessica Stahl did her own survey to find out how American students and foreign students relate to each other. More than 100 students, about half of them American, answered her online questions.

Half of the international students and 60% of the Americans said they related as well or better to the other group than to their own group.

Professor Gareis says: "International students who make friends with host nationals are, overall, more satisfied with their stay in the host country. They have better language skills, they have better academic performance and they have better attitudes toward the host country."

1.What can be the best title for the text?

A. Making Friends Is Not Always Easy for Foreign Students

B. Students from East Asia Are Not Good at Making Friends

C. International Education Industry in Australia and America

D. The Relation between Foreign Students and Host Countries

2.Professor Gareis tends to think that ___________.

A. culture shock should be blamed for many levels of American culture

B. foreign students don’t know small talks mean a lot to Americans

C. foreign students should learn some basic social skills first of all

D. foreign students have difficulty making friends for different reasons

3.How did Jessica Stahl carry out her survey?

A. By doing questionnaires from Students Union

B. By asking questions on the Internet

C. By forming the students into groups

D. By doing a survey through VOA

4.Which of the following statements will the writer probably agree with?

A. International students like to make more friends in their own group

B. International students are more likely to remain in the host country after graduation

C. Students who make more friends at home have better academic performance

D. Students who make friends in their host countries feel happier with their experience

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科目：高中英語 來源：新人教版2017-2018學(xué)年高二必修5英語：Unit2 The United Kingdom單元練習(xí) 題型：閱讀理解

London Underground

The world's first subway was built in London in 1863. At the time, the government was looking for a way to reduce traffic problems in the city of London. The poor areas of the city were so crowded with people that it was almost impossible for horse carriages to get through. The city officials were interested in trying to make it possible for workers to live outside of London and travel easily to work each day. If people had a cheap and convenient way that they could depend on to go to and from work, they would relocate their homes outside of the city. This would help ease(減輕) the pressure of too many people living in the poor parts of London. From these problems, the idea of the London Underground, the first subway system, was born.

The plans for building the Underground met with several problems and delays, but the fast track was finally opened in January 1863. A steam train pulled the cars along the fast underground track which was 6 kilometers (3.7 miles) long. About 30,000 people got on the subway the first day. Riders were treated to comfortable seats (standing up while the train was moving was not allowed), and pleasant decorations inside each of the cars. However, the smoke from the engine soon filled the air in the tunnels with ash and soot(煤灰), as well as chemical gases. Fans had to be put in the tunnels later to keep the air clean enough for people to breathe. Even with its problems, riding in the Underground did catch on. It carried 9 million riders in its first year.

1.What led the British government to build the London Underground?

A. Traffic jams and pollution.

B. Population and pollution.

C. Overcrowding and traffic jams.

D. The poverty and subway problems.

2.How did the London Underground solve the smoke problem?

A. It made the tunnels larger.

B. It put fans in the tunnels.

C. It cleaned the chemical gases in the tunnels.

D. It reduced the number of passengers riding in the train.

3.The underlined phrase “catch on” most probably means “  ”.

A. be troublesome

B. become popular and fashionable

C. keep up with

D. seize

4.Which of the following is TRUE?

A. To relocate the workers' homes outside London, the government built the subway.

B. There were so many problems and delays that in 18th century the first subway opened.

C. The subway greatly eased the pressure of traffic.

D. There were not enough seats for the passengers the first day the subway opened.

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