题目内容

See a cellphone cover that you like on Taobao? Forget about placing an order, paying the bill online and waiting for days for it to be delivered to you. In the near future, you'll be able to get it in minutes just by hitting “print” on your computer. You might find it hard to believe that you could actually “print” an object like you would draw a picture. But it is not that hard to understand how it would work. Just as a traditional printer sprays ink onto paper line by line, modern 3D printers spread material onto a surface layer by layer, from the bottom to the top, gradually building up a shape.

Instead of ink, the materials the 3D printer uses are mainly plastic, resin(树脂) and certain metals. The thinner each layer is—from a millimetre to less than the width of a hair—the smoother and finer the object will be. This may sound like a completely new technology, but the truth is that 3D printing has been around since the late 1980s. Back then, it was barely affordable for most people, so few knew about it.

Last year, though, saw a big change in the 3D printing industry—printers became much cheaper. For example, 10 years ago a desktop 3D printer might have cost £20,000, while now they cost only about £1,000, according to the BBC. Taken out of the factory and introduced to more diverse and common uses, 3D printing can create just about anything you can think of—flutes, bikinis, jewelry, aircraft parts and even human organs. In fact, scientists from Cornell University in New York have just made an artificial ear using a 3D printer, according to Science Daily. The fake ear looks and acts exactly like a natural one.

However, as 3D printing becomes more common, it may bring about certain problems—such as piracy. “Once you can download a coffee maker, or print out a new set of kitchen utensils (餐具) on your personal 3D printer, who will visit a retail store again?” an expert in 3D printing told Forbes News. Even more frightening, what if anyone in the world could use a 3D printer to print out a fully functioning gun?

1.According to the article, in the future, the 3D printing technology will _______.

A. enable people to make better purchases online

B. change the way we make many products

C. be applied as widely in our daily life as computers

D. shorten the time it takes for people to get what they buy online

2.What happened in the 3D printing industry last year?

A. The 3D printing technology was taken out of the factory.

B. The 3D printing technology began to be used in various fields.

C. The 3D printer was used for medical treatment for the first time.

D. The 3D printer became more affordable for consumers(消费者).

3.What is the best title of the passage?

A. Great Demand for 3D Printers

B. Technology in the Future

C. Online Shopping Disappearing

D. Printing out Everything

4.How is the last paragraph developed?

A. By giving examples.

B. By making comparisons.

C. By analyzing the cause and effect.

D. By using figures.

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The deadliest Ebola outbreak in history that has so far killed almost 1000 people in Guinea, Liberia, Sierra Leone and Nigeria in West Africa has caused fear around the world.

The outbreak is unprecedented(空前的)both in infection numbers and in geographic scope. Officials from the World Health Organization (WHO) said earlier this month the outbreak “is moving faster than our efforts to control it”, reported CNN. So far, the battle against the virus doesn’t appear to be slowing down.

The Ebola virus is terrifying no matter where it strikes: It’s a disease with no cure that causes headaches and fever, severe diarrhea(腹泻), vomiting and bleeding and has been known to kill up to 90 percent of its victims.

It is understandable for people to be panicked, but those living outside Africa shouldn’t be particularly concerned about contracting the virus, says a Washington Post article.

This is because transmission of Ebola requires direct contact with an infected person’s blood, vomit or other bodily fluids during the period that he or she is contagious(接触传染的). It is something that is extremely unlikely for anyone but healthcare workers. The virus is not spread by coughing or sneezing.

Media outlets in the US and the UK are using terrifying headlines, wrongly claiming that people infected with the virus have traveled to their countries.

James Ball at The Guardian says the Ebola outbreak in Africa is tragic, but it is important to keep a sense of proportion. Other infectious diseases, including common influenza, are far, far deadlier.

1.What does the author say about the Ebola outbreak in West Africa?

A. It has caused thousands of African deaths.

B. Its spreading speed is beyond people's imagination.

C. It has already traveled to the US and the UK.

D. The fight against it is slowing down.

2.The Ebola virus is terrifying because ________.

A. it cannot be cured at the moment

B. it is easily infected

C. it spreads faster than any other infectious disease

D. it has caused more deaths than other infectious diseases

3.The underlined phrase in the last paragraph means

A. keep a secretB. stay calm

C. keep silentD. stay away from it

4.What is the author's attitude towards people's panic?

A. Objective.B. Supportive.C. Doubtful.D. Understandable.

DOGS DRIVE CAR

Auckland, New Zealand

After two months of learning, Monty, and Porter were able to drive an automobile around a racetrack. “We wanted to prove how smart rescue dogs are,”animal behaviorist Mark Vette says. Vette first used voice commands and treats to teach the dogs how to turn a steering wheel and how to change gear (换挡).

The dogs’ ride only accelerated up to 7.5 miles an hour, and trainers could stop the auto using a remote control.

GOLDEN ZEBRA

Kailua-Kona, Hawaii

Zoe the zebra’s markings are special. The animal has white and golden stripes. Zoe’s appearance resulted from a rare condition called amelanosis (黑素缺失症). Her body doesn’t make enough melanin, the substance in an animal’s skin and hair cells that produces color. “Only 25 other golden zebras are known to exist in the world,” says Ann Goody, who runs the wildlife refuge where Zoe lives. In the wild, life may be difficult for animals with amelanosis because predators (捕猎者) can easily spot them. But Zoe is protected at her refuge.

COCKATOO MAKES TOOLS

Vienna, Austria

When Figaro the cockatoo spots food lying just out of reach from his cage, he builds a tiny wooden tool to sweep the tasty prize in his way.

The bird first revealed his talent when a stone he was playing with rolled out of his cage. The cockatoo couldn’t reach the stone. So he flew away and returned with a small branch, slipping it through the fence to slide the stone toward him.

Wondering if he would do it again, scientists placed a nut exactly where the stone had been. This time, Figaro pulled out a small piece of wood in his cage and dragged the nut toward him.

1.If Zoe the zebra is set free in the wild, she will ________.

A. meet no natural predators

B. not get along with other zebras

C. manage to make enough melanin

D. be easily found for her appearance

2.What’s special about Figaro the cockatoo?

A. He is particular about his food.

B. He is extremely fond of stones.

C. He is good at drawing support from outside forces.

D. He can tell the difference between stones and nuts.

3.What is the text mainly about?

A. Amazing animals.

B. Ways to help animals.

C. Animals’ unique talents.

D. Tips on training animals.

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