题目内容

When a leafy plant is under attack, it doesn’t sit quietly. Back in 1983,two scientists,Jack Schultz and Ian Baldwin,reported that young maple trees getting bitten by insects send out a particular smell that neighboring plants can get. These chemicals come from the injured parts of the plant and seem to be an alarm.What the plants pump through the air is a mixture of chemicals which are called VOCs for short.

Scientists have found that all kinds of plants give out VOCs when being attacked .It’s a plant’s way of crying out.But is anyone listening?Exactly.Because we can watch the neighbours react.

Some plants release smelly chemicals to keep insects away.But others do double duty .They pump out perfumes designed to attract different insects who are natural enemies to the attackers.Once they arrive,the tables are turned .The attacker who was lunching now becomes lunch.

In study after study,it appears that these chemical conversations help the neighbors .The damage is usually more serious on the first plant,but the neighbors ,relatively speaking ,stay safer because they heard the alarm and knew what to do.

Does this mean that plants talk to each other? Scientists don’t know. Maybe the first plant just made a cry of pain or was sending a message to its own branches, and so, in effect, was talking to itself. Perhaps the neighbors just happened to “overhear” the cry. So information was exchanged, but it wasn’t a true communication.

Charles Darwin, over 150 years ago, imagined a world far busier, noisier and more intimate(亲密的) than the world we can see and hear. Our senses are weak. The world is .

1.Does a leafy plant sit quietly when it is under attack?

2.What does a plant do when it is under attack?

3.How can scientists know that there is someone listening to the crying?

4.What does the author mean by “the tables are turned” in paragraphs 3?

5.From the scientists' studies, can plants protect themselves against insects or really talk to each other?

6.What can be filled in the blank at end of the passage?

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Artificial intelligence(人工智能), or AI in short, is the science of giving computers and machines ability to think and work like humans. AI scientists and engineers have made a lot of cool technologies. AI is rapidly catching up with the human ability to read faces. As a result, facial recognition(面部识别)is used a lot in the world. Chinese police use this technology to identify criminals(罪犯).Once they caught a criminal when he attended a concert. It also checks the ID of ride-hailing(网约车)drivers and lets people pay for things with a smile.

AI is also used in self-driving cars, which are believed to be the future of driving. Most drivers may wave or nod at passers-by to let them cross the street, but self-driving cars don't have this ability. Carmakers are testing a light signal system to help them "speak" to humans. The system can show what self-driving cars will do. For example, if a driverless car is yielding(让路), it will flash two white lights side to side. A rapidly flashing light tells passers-by that the car is about to speed up.

Service Robots also show you how powerful AI is. Imagine this—you come back home from school and your robot housekeeper is waiting for you at the door. After dinner, he teaches you to play the piano, just like a real music teacher. Such thoughts will soon happen in the real world. In the future, more and more service robots will become good home helpers. AI is so powerful that it can help human beings and even replace us in many jobs.

1.What does the underlined word "identify" mean in Paragraph 2 probably mean?

A.To let somebody know his mistakes.

B.To come to realize and tell who is who.

C.To take somebody to the police station.

D.To tell somebody something important.

2.According to the passage, what is facial recognition used for?

A.Driving cars. B.Making people smile.

C.Calling the police. D.Checking people's information.

3.Which technology has been used in real life according to the passage?

A.Service Robots at school. B.Robots as ride-hailing drivers.

C.Facial recognition for payment. D.Light signals for self-driving cars.

4.According to the passage, how many ways can AI be used in the future?

A.One. B.Two C.Three D.Four.

5.What can we learn from the passage?

A.People use AI in many different ways.

B.AI will take the pace of human beings in all jobs.

C.Self-driving cars will be able to talk like humans.

D.A criminal was caught for inventing facial recognition.

Choose the best answer(根据短文内容,选择恰当答案)

Lao Wang is Jack’s Chinese friend. One day Jack was invited to his home for dinner. After they enjoyed the dinner, Jack made a short speech and then sent Lao Wang a clock. “I’d like you to accept this small clock,” said Jack. “Thank you.” Lao Wang thanked him, but he looked unhappy and put the clock in another room. “Don’t you like it?” Jack said. “Oh, no. Thank you.” Lao Wang answered. Later, another guest said to Jack, “Giving a clock to a friend is unlucky in Chinese culture. The word for clock ‘Zhong’ also means the end of life.”

Jack has been visiting China for many years and made quite a few Chinese friends. He told me that he knows something about China and that he is used to differences between China and America, but he has never heard about clocks being unlucky. “Clock is a typical (典型的) gift in America, everybody would be pleased to accept it,” Jack said to me sadly. “So we should be more careful about the different culture and now we have a lot to learn from the Chinese,” I said.

Indeed cultural differences are part of the fun of traveling. To do as the Romans do, you have to understand the local culture and customs.

1.Jack was invited to ______ for dinner one day.

A.Lao Wang’s B.my home C.a restaurant D.a hotel

2.Sending a clock means ______ in China.

A.happy B.unhappy C.lucky D.unlucky

3.______ is very important to travelers.

A.To know how to send a gift B.To invite guests for dinner

C.To give clocks to others D.To know cultural differences

4.The word “accept” means _______ in Chinese.

A.需要 B.接受 C.喜欢 D.拒绝

5.From the passage, we know Jack is probably _______.

A.Chinese B.Roman C.American D.Japanese

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