In a study published in the U. S. journal Science, researchers from the Chinese Academy of Agricultural Sciences(CAAS) and the University of Florida identified the chemical combinations and genetic recipe for better tomato flavor(味道).

“In recent years, consumers often complain that the modern tomato is less flavorful than it once was” said co-principal researcher Sanwen Huang. “Our results provide a practical road map for breeding tomato varieties with better flavor.”

For the study, a 170-person consumer group was created to evaluate 160 tomatoes representing 101 varieties, based on qualities such as “overall liking” and “flavor degree”. The results pointed to dozens of chemical compounds of interest, and further research using a statistical model discovered 33 flavor compounds connected with consumer liking, such as glucose(葡萄糖). The reason why modern tomatoes don’t taste good anymore is that a total of 13 of these flavor-associated compounds “were significantly reduced in modern varieties,” their paper wrote. Moreover, the researchers found that smaller fruit tended to have greater sugar content, suggesting that “selection for more sizable tomatoes has cost sweetness and flavor”.

Based on this knowledge, Huang and Professor Harry Klee of the University of Florida studied the whole genomes of 398 varieties of tomato, identifying about 250 positions of genes on a chromosome(染色體), which controlled tomato flavor.

“We’re just fixing what has been damaged over the last half century to push them back to where they were a century ago,” said Klee in a statement. “We can make the supermarket tomato taste noticeably better.” Klee said new tomato varieties with better flavor could be ready in three to four years. In addition, “the genes and pathways identified here in the tomato almost certainly point to pathways worth researching for improvement of flavor quality in other fruit crops,” they wrote.

1.According to the text, the study ________.

A. was carried out just through a survey

B. was conducted by Chinese researchers themselves

C. was completely focused on the genes of different tomatoes

D. was done with the background of declining flavor of tomatoes

2.The researchers have found that ________ in the study.

A. bigger tomatoes are much sweeter

B. some genetic positions affect the taste of tomatoes

C. some chemical compounds make tomatoes less tasty

D. a total of 13 flavor-associated compounds make tomatoes appealing in taste

3.What is the influence of the study according to the text?

A. The study lays the foundation for further researches to improve other fruit crops’ flavor.

B. The study makes it possible for us to have noticeably more tasty tomatoes next year.

C. The study provides a road for where to plant tomatoes with better flavor.

D. The study has fixed all the genes of existing tomatoes.

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科目：高中英語 來源：2017屆重慶市高三下學期第一次月考英語試卷（解析版） 題型：閱讀理解

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C. He told no one about his disease.

D. He was carefully attended by the nurses on his deathbed

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增加：在缺詞處加一個漏字符號(∧)，并在其下面寫出該加的詞。

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Now, this unforgettable lesson still encourages me to be an active learner where I go.

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1．詞數(shù)100左右；

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The Cambridge Science Festival Curiosity Challenge

Dare to Take the Curiosity Challenge!

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Students who enter the Curiosity Challenge and are selected as winners will be honored at a special ceremony during the CSF on Sunday, April 21st. Guest speakers will also present prizes to the students. Winning entries will be published in a book. Student entries will be exhibited and prizes will be given. Families of those who take part will be included in the celebration and brunch will be served.

Between March 10th and March 15th, eac h winner will be given the specifics of the closing ceremony and the Curiosity Challenge celebration. The program guidelines and other related information are available at: http:// cambridgesciencefestival.org.

1.Who can take part in the Curiosity Challenge?

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2.When will the prize-giving ceremony be held?

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C. On March 15th. D. On April 21st.

3.What type of writing is this text?

A. An exhibition guide. B. An art show review.

C. An announcement. D. An official report.

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科目：高中英語 來源：江西省2016-2017學年高一下學期第一次月考英語試卷 題型：閱讀理解

Flight cancellations(取消) and loss of luggage can ruin even the best-planned holiday. The key to a stress-free trip is having a backup plan.

Fly non-stop. The worst problems involve connections, so it is important to take non-stop flights whenever possible. If you do have to make a connection, try to route through a southern city, where snowstorms and de-icing delays will be less likely. Always allow at least two to three hours for flight connections.

Check the weather. Check the weather in your connecting city, not just the arrival and departure city. If your departure flight is cancelled because of weather, you can go home or back to your hotel. Airlines promise to get you on the next available flight, not the next flight. That could be several days later on a sold-out holiday weekend.

Go early. The earlier in the day you fly, the better your chance of getting rebooked the same day after a missed connection. It will also put you ahead of stranded(滯留的) passengers who arrive later.

Rebook immediately. As soon as your flight is delayed or cancelled, get on the phone and rebook your flight instead of waiting at the ticket counter. If your rebooking is delayed, call or ask your travel agent to find a seat on another carrier, and then ask your original carrier to endorse your ticket to the new airline. Airlines are not required to do this but often do. Learn more at www. dot. gov/ airconsumer/ fly-rights.

Ship bags. A few days before your flight, ship suitcases or holiday gifts to your destination by a documented express service. It’s preferable to losing bags because of re-routed flights and sometimes cheaper than paying airline overweight bag fees.

Know your rights. Airlines are not required to compensate passengers for delayed or cancelled flights, but it never hurts to ask for goodwill vouchers(折扣) for meals, taxis or a room.

1.When making a flight connection, it’s common that you’ll___________.

A. stop in the south B. choose a good city without snowstorm

C. be trapped in the storm D. wait for two or three hours

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3.The underlined word “compensate” in the last paragraph can be replaced by “___________”.

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4.What’s the best title of the passage?

A. The Worst Problem in the Trip.

B. The Preparation Before the Flight Trip.

C. How to Book the Plane Ticket.

D. How to Plan the Holiday.

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