Plants can’t communicate by moving or making sounds, as most animals do. Instead, plants Produce volatile compounds, chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from volatile compounds that the plant produces to attract insects such as Bugs and bees.

Plants can also detect volatile compounds produced by other plants. A tree under attack by Hungry insets, for instance, may give off volatile compounds that let other trees know about the Attack. In response, the other trees may send off chemicals to keep the bugs away ——or even  Chemicals that attract the bugs’ natural enemies.

Now scientists have created a quick way to understand what plants are saying: a chemical Sensor（传感器）called an electronic nose. The “e-nose” can tell compounds that crop plants make When they’re attacked Scientists say the e-nose could help quickly detect whether plants are being Eaten by insects. But today the only way to detect such insects is to visually inspect individual Plants. This is a challenging task for managers of greenhouses, enclosed gardens than can house Thousands of plants.

The research team worked with an e-nose than recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.

To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then scientists collected samples of air around damaged leaves from each type of crop, These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch（打孔器）. The e-nose, it turns out, could identify healthy cucumber, pepper and tomato plants based on The volatile compounds they produce, It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage ---- by insects or with a hole Punch ---- had been done to the tomato leaves.

With some fine-tuning, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareva, a biochemist at Purdue University in West Lafayette, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.

We learn from the text that plants communicate with each other by____.

A. making some sounds        B. waving their leaves

C. producing some chemicals   D. sending out electronic signals

What did the scientists do to find out if the e-nose worked?

A. They presented it with all common crops.

B. They fixed 13 sensors inside the device.

C. They collected different damaged leaves.

D. They made tests on damaged and healthy leaves.

According to the writer, the most amazing thing about the e-nose is that it can___.

A. pick out ripe fruits

B. spot the insects quickly

C. distinguish different damages to the leaves

D. recognize unhealthy tomato leaves

We can infer from the last paragraph that the e-nose_____.

A. is unable to tell the smell of flowers

B. is not yet used in greenhouses

C. is designed by scientists at Purdue

D. is helpful in killing harmful insects

  Plants can’t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds, chemicals that easily change from a liquid to a gas .A flower’s sweet smell, for example, comes from volatile compounds that the plant produces to attract insects such as bugs and bees.

  Plants can also detect volatile compounds produced by other plants. A tree under attack by hungry insects, for instance, may give off volatile compounds that let other trees know about the attack, In response, the other trees may send off chemicals to keep the bugs away- or even chemicals that attract the bugs’ natural enemies.

  Now scientists have created a quick way to understand what plants are saying: a chemical sensor(传感器) called an electronic nose. The “e-nose” can tell compounds that crop plants make when they’re attacked. Scientists say the e-nose could help quickly detest whether plants are being eaten by insects, But today the only way to detect such insects is to visually inspect individual plants. This is a challenging task for managers of greenhouses, enclosed gardens that can house thousands of plants.

  The research team worked with an e-nose that recognizes volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds. Based on these interactions, the e-nose gives off electronic signals that the scientists analyze using computer software.

  To test the nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all common greenhouse crops. Then the scientists collected samples of air around damaged leaves from each type of crop. These plants had been damaged by insects, or by scientists who made holes in the leaves with a hole punch (打孔器).

  The e-nose, it turns out, could identify healthy cucumber, pepper and tomato plants based on the volatile compounds they produce. It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage by insects or with a hole punch had been done to the tomato leaves.

  With some fine tuning, a device like the e-nose could one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this could also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareve, a biochemist at Purdue University in West Lafayette, Ind. who studies smells of flowers and plants. Hopefully, scientists believe, the device could bring large benefits to greenhouse managers in the near future.

49. We learn from the text that plants communicate with each other by______.

A. making some sounds       B. waving their leaves

C. producing some chemicals  D. sending out electronic signals

50. What did the scientists do to find out if the e-nose worked?

A. They presented it with all common crops..

B. They fixed 13 sensors inside the device.

C. They collected different damaged leaves.

D. They made tests on damaged and healthy leaves.

51. According to the writer, the most amazing thing about the e nose is that it can ______.

A. pick out ripe fruits

B. spot the insects quickly

C. distinguish different damages to the leaves

D. recognize unhealthy tomato leaves

52. We can infer from the last paragraph that the e-nose_____.

A. is unable to tell the smell of flowers

B. is not yet used in greenhouses

C. is designed by scientists at Purdue

D. is helpful in killing harmful insects

It’s such a happy-looking library, painted yellow, decorated with palm-tree stickers and sheltered from the Florida sun by its own roof. About the size of a microwave oven, it’s pedestrian-friendly, too, waiting for book lovers next to a sidewalk in Palm Beach country Estates, along the northern boundary of Palm Beach Gardens.
It’s a library built with love.
A year ago, shortly after Janey Henriksen saw a Brian Williams report about the Little Free Library organization, a Wisconsin-based nonprofit that aims to promote literacy and build a sense of community in a neighborhood by making books freely available, she announced to her family of four, “That’s what we’re going to do for our spring break!”
Son Austin, now a 10th-grader, didn’t see the point of building a library that resembles a mailbox. But Janey insisted, and husband Peter unwillingly got to work. The 51-year-old owner of a ship supply company modified a small wooden house that he’d built years earlier for daughter Abbie’s toy horses, and made a door of glass.
After adding the library’s final touches (装点), the family hung a signboard on the front, instructing users to “take a book, return a book,” and making the Henriksen library, now one of several hundred like it nationwide and among more than 2,500 in the world, the only Little Free Library in Palm Beach County.
They stocked it with 20 or so books they’d already read, a mix of science fiction, reference titles, novels and kids’ favorites. “I told them, keep in mind that you might not see it again,” said Janey, a stay-at-home mom.
Since then, the collection keeps replenishing (补充) itself, thanks to ongoing donations from borrowers. The library now gets an average of five visits a day.
The project’s best payoff, says Peter, are the thank-you notes left behind. “We had no idea in the beginning that it would be so popular.” (317 words)
【小题1】In what way is the library “pedestrian-friendly”?

Plants can’t communicate by moving or making sounds, as most animals do. Instead, plants produce volatile compounds (挥发性化合物) —— chemicals that easily change from a liquid to a gas. A flower’s sweet smell, for example, comes from such volatile compounds to attract insects such as bugs and bees.
Plants can also discover  volatile compounds produced by other plants. A tree under attack by hungry insets, for instance, may give off these chemicals in order to let other trees know about the attack. In response, the other trees may send off their chemicals to keep the bugs away —— or even chemicals that will attract the bugs’ natural enemies.
Now scientists have created a quick way to understand what plants are saying: a chemical sensor (传感器) called an “electronic nose”. The “e-nose” can tell such compounds as plants make. When plants are attacked, scientists say, the e-nose could help quickly decide whether plants are being eaten by insects. But today, the only way to spot such insects is to inspect individual plants by observing them. This is a challenging task for managers of greenhouses, including those that can house thousands of plants. The research team is working with an e-nose that can recognize volatile compounds. Inside the device, 13 sensors chemically react with volatile compounds based on the interactions (相互作用), and then the e-nose will give off electronic signals that the scientists can analyze by using computer software.
To test the e-nose, the team presented it with healthy leaves from cucumber, pepper and tomato plants, all being common greenhouse crops. Then scientists collected samples of the air around damaged leaves from each type of crop. These plants had been damaged either by insects or by scientists who made holes in the leaves with a hole punch (打孔器).
The e-nose, it turns out, can identify healthy cucumber, pepper and tomato plants based on the volatile compounds they produce. It could also identify tomato leaves that had been damaged. But even more impressive, the device could tell which type of damage —— by insects or with a hole punch —— had been done to the tomato leaves.
With some fine-tuning (微调), a device like the e-nose can one day be used in greenhouses to quickly spot harmful bugs, the researchers say. A device like this can also be used to identify fruits that are perfectly ripe and ready to pick and eat, says Natalia Dudareva, a biochemist at Purdue University in West Lafayette, India, who studies smells of flowers and plants. Hopefully, scientists believe, the device can bring large benefits to greenhouse managers in the near future.
【小题1】We learn from the text that plants communicate with each other by ______.

It was the afternoon of December 24, the day before Christmas, and as the newest doctor in our office, I had to work. The only thing that brightened my day was the beautifully decorated Christmas tree in our waiting room and a gift sent to me by a fellow I was dating—a dozen long-stemmed red roses.
As I was cleaning my office, I was told a lady urgently needed to speak with me. As I stepped out, I noticed a young, tired-looking woman with a baby in her arms. Nervously, she explained that her husband—a prisoner in a nearby prison—was my next patient. She told me she wasn’t allowed to visit her husband in prison and that he had never seen his son. Her request was for me to let the boy’s father sit in the waiting room with her as long as possible before I called him for his appointment. Since my schedule wasn’t full, I agreed. After all, it was Christmas Eve.
A short time later, her husband arrived—with chains on his feet and hands, and two armed guards as bodyguards. The woman’s tired face lit up like our little Christmas tree when her husband took a seat beside her. I kept glancing out to watch them laugh, cry and share their child. After almost an hour, I called the prisoner back to my office. The patient seemed like a gentle and modest man. I wondered what he possibly could have done to be held under such conditions. I tried to make him as comfortable as possible.
At the end of the appointment, I wished him a Merry Christmas—a difficult thing to say to a man headed back to prison. He smiled and thanked me. He also said he felt saddened by the fact that he hadn’t been able to get his wife anything for Christmas. On hearing this, I was inspired with a wonderful idea.
I’ll never forget the look on both their faces as the prisoner gave his wife the beautiful, long-stemmed roses. I’m not sure who experienced the most joy—the husband in giving, the wife in receiving, or myself in having the opportunity to share in this special moment.
67.What can be inferred from the first paragraph?
A. The writer was a newcomer to her office. 
B. A fellow sent her a dozen red roses as Christmas present.
C. She was in low spirits because she had to work before Christmas.
D. She was at work with a light heart.
68. The young woman came to the writer’s office for the purpose of         .
A. having her baby examined      
B. giving her husband a chance to make his escape
C. having her husband examined  
D. getting a chance for her family to get together
69.The underlined part in Paragraph 3 most probably means          . 
A. to be sent to hospital            B. to be separated from his family
C. to be comfortable                   D. to become a prisoner
70. What does the writer learn from the story?
A. The wife experienced the most joy in receiving. 
B. An act of kindness can mean a lot.
C. The prisoner was treated with mercy.      
D. Whoever breaks the law should be punished.