Following news of the potential for life on the recently-discovered TRAPPIST-1 system, there may be another competitor ready to take its place.With the help of the Cassini spacecraft, NASA (National A 题目和参考答案——青夏教育精英家教网—

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Following news of the potential for life on the recently-discovered TRAPPIST-1 system, there may be another competitor ready to take its place.

With the help of the Cassini spacecraft, NASA (National Aeronautics and Space Administration) scientists have picked up the first evidence that chemical reactions are taking place deep below the surface of Enceladus, Saturn’s (土星的) sixth-largest moon. This means that there could be life in Enceladus’ warm underground seas.

An early study found that liquid oceans exist miles below Enceladus’ surface. But to reveal what is happening down there, scientists must rely on the plumes (股) of water that spray (喷射) through cracks in Enceladus’ icy surface. In October 2015, NASA sent Cassini into a deep dive into one of the plumes.

Cassini’s findings, published on April 13 in the journal Science, showed that hydrogen (氢) not only exists on Enceladus, but is also responsible for a chemical reaction between hot rocks and water in the ocean beneath its surface.

This same process on Earth provides energy for entire ecosystems around volcanic vents (火山口). There, tiny creatures are able to survive without sunlight, using hydrogen and carbon dioxide as fuel in a process known as “methanogenesis (甲烷生成)”.

The discovery of this chemical energy source on Enceladus means it could be a very good candidate to host life.

“Confirmation (确认) that the chemical energy for life exists within the ocean of a small moon of Saturn is an important milestone (里程碑) in our search for habitable (可居住的) worlds beyond Earth,” Linda Spilker, Cassini project scientist at NASA, told the Daily Mail.

Alien life was once only thought possible on habitable planets within the “Goldilocks zone” – far enough from our sun not to be a fireball, but not so far as to be freezing.

Research on Enceladus is still in its early stages, but the recent findings have important meanings for future exploration.

“At present, we know of only one genesis (诞生) of life, the one that led to us,” David Rothery, professor of planetary geosciences (行星与地球科学) from the Open University in the UK, told The Telegraph.

“If we knew that life had started independently in two places in our solar system, then we could be pretty confident that life also got started on some of the tens of billions of planets and moons around other stars in our galaxy,” he said.

1.What is the article mainly about?

A. The connection between the TRAPPIST-1 system and Enceladus.

B. The potential for life on Saturn’s moon, Enceladus.

C. The chemical energy source on Enceladus.

D. Scientists’ constant search for life in the solar system.

2.Scientists assume that there could be life on Enceladus because ______.

A. there is evidence of a warm ocean under Enceladus’ surface

B. hot rocks and water have been discovered on Enceladus

C. hydrogen discovered on Enceladus could be a chemical energy source

D. the entire ecosystems of Enceladus are somewhat similar to those of Earth

3.According to David Rothery, the recent findings on Enceladus could mean that ______.

A. there is only one genesis of life in our galaxy

B. there could be many habitable planets, but all in the “Goldilocks zone”

C. it won’t be long before scientists find a habitable planet beyond Earth

D. alien life could exist on some other planets if it existed on Enceladus

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Please go on trying.I’m sure the efforts you are________will pay off.

A. doing B. giving

C. making D. sparing

Not until we saw the manager did we know that the bank ________the company for the purpose of reducing its borrowings.

A. took part in B. caused damage to

C. put pressure on D. drew attention to

Once there lived a rich merchant（商人）and a poor shoemaker in the same house.The merchant occupied the second floor,____the shoemaker lived and worked in a small room on the first floor.The shoemaker was one of the____persons on earth.He worked from morning till night,singing merrily.His heart was filled with____,whenever he saw the boots and shoes____.Now the merchant upstairs was so rich that he____knew how much wealth he had.He was always__ over his gold and silver coins far into the night.Even in bed his uneasiness（不安）about his riches kept him____.When at last he had been asleep for an hour or two,up came the song of the happy shoemaker,who was an____riser.It continued all day and was a (n)____to the merchant.Day by day the merchant grew more and more tired through want of____.He asked a wise friend of his how he could put an____to the shoemaker’s song.“Well,if I were you,I would give the shoemaker a hundred pounds,”answered his friend.“You are rich enough to do that,I suppose.Ask for nothing in __.Simply give the money.”The merchant____the advice.

When the shoemaker____the bag that had been sent by the merchant,he was____to find shining coins.“I must hide this from the eyes of my neighbors.If they see it,they will think that I have stolen it,”he thought.“I will____it away even from my wife.”So he hid the bag of money under the floor.From then on he____his neighbors as much as he could.His wife who had been the best____to him,became troublesome.Now his mind was too much set on the money bag to___to his work with diligence（勤劳）.He could not sing merrily now.___he thought of the money bag,he became uneasy and unhappy.

1.A. for B. therefore C. while D. however

2.A. highest B. happiest C. richest D. shortest

3.A. smile B. sorrow C. sadness D. joy

4.A. being repairing B. repair C. to repair D. to be repaired

5.A. always B. completely C. hardly D. entirely

6.A. hiding B. counting C. fighting D. figuring

7.A. awake B. nervous C. frightened D. asleep

8.A. early B. happy C. noisy D. late

9.A. threat B. matter C. trouble D. alarm

10.A. sympathy B. understanding C. sleep D. treatment

11.A. end B. notice C. information D. stop

12.A. trouble B. need C. turn D. return

13.A. refused B. agreed C. asked D. followed

14.A. stole B. opened C. received D. carried

15.A. exciting B. amazed C. ashamed D. disappointed

16.A. throw B. keep C. give D. remain

17.A. avoided B. thanked C. helped D. attracted

18.A. companion B. fellow C. shoemaker D. merchant

19.A. tend B. turn C. attend D. come

20.A. Wherever B. Whatever C. Whenever D. However

假定你是李华，校读书俱乐部负责人。俱乐部将在下周三下午三点在报告厅进行英语朗读比赛(recitation contest)。请你给外教Tom写一份电子邮件。内容如下:

1. 邀请他担任比赛评委；

2. 问他届时是否有空出席；

3. 请他向学生推荐合适的文学作品。

注意:

1. 词数80左右。

2. 可适当增加细节，以使行文连贯。

___________________________________________________________________________________________

________________________________________________________________________

Last Friday when Jose Rodriguez , a 5-year-old white boy, asked his mother Lydia Rodriguez if he could get his blonde hair cut like his black friend Reddy’s, and of course his mother agreed. For a very ____ reason the two pre-school friends decided to ____ their teacher with matching haircuts.

Jose ____ that if he and Reddy had the same haircut, no one would be able to ____ them. Reddy apparently thought this trick was ____ as well.

“It is just two ____ boys. Obviously, they see they are different colors, they just don’t care. It is not ____ , Rodriguez said. She sees Jose’s inability to see a ____ between himself and his friend as a parenting win. “I just taught him to ____ everyone the same,” she said.

The teacher played along and ____ she was talking to Jose when Reddy arrived before Jose, he told the teacher and his _____he was Jose.

On Monday, Rodriguez ____ the story on the Facebook.78,000 people ____ it and the story has gone viral（疯传）. On the post she wrote: “If this isn’t proof that ____ and prejudice is something that is ____ , I don’t know what is. Their ____ is the only difference Jose sees in the two of them. Though Jose loves ____ himself on TV and the Internet, he remains unsure why his haircut became such a big ____ .

“He still has no idea why people ____ so much”, Rodriguez said. “He wanted to ____ Reddy and now he thinks they look the same.”

1.A. wrong B. obvious C. sweet D. funny

2.A. trick B. entertain C. surprise D. frighten

3.A. feared B. decided C. promised D. admitted

4.A. tease B. substitute C. persuade D. distinguish

5.A. simple B. amusing C. perfect D. stupid

6.A. innocent B. naughty C. happy D. clever

7.A. ridiculous B. important C. reasonable D. convincing

8.A. friendship B. cooperation C. respect D. difference

9.A. praise B. blame C. love D. attend

10.A. confirmed B. pretended C. reminded D. explained

11.A. classmates B. parents C. relatives D. guests

12.A. downloaded B. commented C. read D. shared

13.A. contributed to B. submitted to C. reacted to. D. turned to

14.A. hate B. identity C. justice D. happiness

15.A. forbidden B. taught C. permitted D. expected

16.A. colors B. characters C. hair D. status

17.A. watching B. introducing C. reflecting D. amusing

18.A. reward B. gift C. debate D. deal

19.A. care B. envy C. talk D. admire

20.A. believe in B. look like C. appreciate D. inspire

1.She had a ____________(painful) in her right side.

2.Most middle-aged pay more attention to ____________(physics)health.

3.Let us combine our two firms against our ______(compete)．

4.How does one gain ____________(admit)to the Buckingham Palace?

5.One of the secrets of good health is ________(regularly)exercise.

6.We want some ____________(volunteer)to help in the hospital.

7.You should take ____________(responsible)for what you said.

8.They attended a party ________(host)by the president of the company.

9.We held a heated discussion on the ________(base)of fact.

10.Would you like to join us in ________(sing)?

He opened his mouth as if ________something.

A. to say B. say

C. saying D. to be said

The sharing economy, represented by companies like Airbnb or Uber, is the latest fashion craze. But many supporters have overlooked the reality that this new business model is largely based on escaping regulations and breaking the law.

Airbnb is an Internet-based service that allows people to rent out spare rooms to strangers for short stays. Uber is an Internet taxi service that allows thousands of people to answer ride requests with their own cars. There are hundreds of other such services.

The good thing about the sharing economy is that it promotes the use of underused resources. Millions of people have houses or apartments with empty rooms, and Airbnb allows them to profit from these rooms while allowing guests a place to stay at prices that are often far less than those charged by hotels. Uber offers prices that are competitive with standard taxi prices and their drivers are often much quicker and more trustworthy.

But the downside of the sharing economy has gotten much less attention. Most cities and states both tax and regulate hotels, and the tourists who stay in hotels are usually an important source of tax income. But many of Airbnb’s customers are not paying the taxes required under the law.

Airbnb can also raise issues of safety for its customers and trouble for hosts’ neighbors. Hotels are regularly inspected to ensure that they are not fire traps and that they don’t form other risks for visitors. Airbnb hosts face no such inspections.

Since Airbnb is allowing people to escape taxes and regulations, the company is simply promoting thefts. Others in the economy will lose by bearing an additional tax burden or being forced to live next to an apartment unit with a never-ending series of noisy visitors.

The same story may apply with Uber. Uber is currently in disputes over whether its cars meet the safety and insurance requirements imposed on standard taxis. Also, if Uber and related services flood the market, they could harm all taxi drivers’ ability to earn a minimum wage.

This downside of the sharing needs to be taken seriously, but that doesn’t mean the current tax and regulatory structure is perfect.

1.What is the positive thing about the sharing economy?

A. It is a global trend.

B. It is beyond regulations.

C. It draws on spare resources.

D. It brings in modest profits.

2.What is the problem with Airbnb customers according to the passage?

A. They are not regularly inspected.

B. They are likely to commit thefts.

C. They are allowed not to pay taxes.

D. They can be noisy to hosts’ neighbours.

3.What is the argument over Uber according to the passage?

A. Whether it guarantees customers’ safety.

B. Whether it provides reliable services.

C. Whether it lowers customers’ expenses.

D. Whether it can compete with standard taxis.

4.What will be talked about in the following paragraphs?

A. Existing regulations and laws.

B. Necessary improvements of current laws.

C. Further development of Airbnb and Uber.

D. More downsides of Airbnb and Uber.

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