Now a group of scientists, including ones from CalTech, MIT and the LIGO Scientific Collaboration finally found the gravitational waves．They announced they were able to see ripples in the structure o 题目和参考答案——青夏教育精英家教网—

题目内容

Now a group of scientists, including ones from CalTech, MIT and the LIGO Scientific Collaboration finally found the gravitational waves(引力波)．They announced they were able to see ripples(波纹) in the structure of spacetime.

What are these gravitational waves? Well, imagine throwing a rock into a pond. When the rock hits the flat surface of the water, it creates ripples. Spacetime is like the surface of the water. So gravitational waves are like the ripples moving out from where the rock hits the water.

It was Einstein who said these gravitational waves should be observable. But these are not huge waves. They are smaller than the size of an atom, which is why it took so long to find them.

Since 2002, scientists have been watching for these gravitational waves, using a giant scientific tool called LIGO. They have been watching two black holes in another galaxy(星系) faraway. The two were spinning around each other, moving closer and closer together. When they finally crashed into each other, gravitational waves were caused. With great power and force, they rang throughout the universe, like a giant bell. Those waves, traveling at the speed of light, finally reached the Earth, some 1.3 billion years later. The National Science Foundation said that each of the black holes was 29 to 36 times the mass of our sun.

This discovery means our understanding of the heavens has changed greatly.

1.The author explains the gravitational waves by ________.

A. presenting recent research findings

B. drawing a vivid picture

C. comparing them to something familiar

D. using proper examples

2.According to the author, finding the gravitational waves means ________.

A. there is a better way to deal with physics problems

B. we have a better understanding of the universe

C. we have reached a new level in earth studies

D. there exists another galaxy in the universe

3.What does the word “they” in Paragraph 4 refer to?

A. The black holes.

B. The gravitational waves.

C. The scientific tools.

D. The galaxies.

4.This passage mainly talks about ________.

A. a new theory of gravitational waves opposite to Einstein’s

B. a description of the scientific research on black holes

C. the relationship between black holes and gravitational waves

D. the discovery of gravitational waves Einstein believed observable

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Terrafugia Inc. said Monday that its new flying car has completed its first flight, bringing the company closer to its goal of selling the flying car within the next year. The vehicle-named the Transition – has two seats， four wheels and wings that fold up so it can be driven like a car. The Transition, which flew at 1,400 feet for eight minutes last month, can reach around 70 miles per hour on the road and 115 in the air. It flies using a 23-gallon tank of gas and bums 5 gallons per hour in the air. On the ground, it gets 35 miles per gallon.

Around 100 people have already put down a $10,000 deposit to get a Transition when they go on sale, and those numbers will likely rise after Terrafugia introduces the Transition to the public later this week at the New York Auto Show. But don’t expect it to show up in too many driveways. It’s expected to cost $279,000.And it won’t help if you’re stuck in traffic. The car needs a runway.

Inventors have been trying to make flying cars since the 1930s, according to Robert Mann, an airline industry expert. But Mann thinks Terrafugia has come closer than anyone to making the flying car a reality. The govemment has already permitted the company to use special materials to make it easier for the vehicle to fly. The Transition is now going through crash tests to make sure it meets federal safety standards.

Mann said Terrafugia was helped by the Federal Aviation Administration’s decision five years ago to create a separate set of standards for light sport aircraft, which are lower than those pilots of larger planes Terrafugia says an owner would need to pass a test and complete 20 hours of flying time to be able to fly the Transition, a requirement pilots would find redatively easy to meet.

1.What is the first paragraph mainly about?

A. The basic data of the Transition. B. The advantages of flying cars.

C. The potential market for flying cars. C. The designers of the Transition.

2.Why is the Transition unlikely to show up in too many driveways?

A. It causes traffic jams. B. It is difficult to operate.

C. It is very expensive. D. It bums too much fuel.

3.What is the government’s attitude to the development of the flying car?

A. Cautious B. Favorable.

C. Ambiguous. D. Disapproving.

4.What is the best title for the text?

A. Flying Car at Auto Show B. The Transition’s Fist Flight

C. Pilots’Dream Coming True D. Flying Car Closer to Reality

假定英文课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下英文。文中共有10处语言错误，每句中最多有两处。每处错误仅涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏词符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下面一横线，并在该词下面写出修改后的词。

注意：1.每次错误及其修改均仅限一词

2.只允许修改10处，多者（从第11处起）不计分。

My parents and I went to the park on last Sunday.There were lots of visitors standing in front of ticket window.We waited for a long time and buy three tickets.In the Tiger Mountain of the park.I was too eager to see the fierce frightening animals that I quickened his steps through the crowd.Unfortunate,I got separated from my parent.I had a hard time looking for them,and I had no luck.Wandering in the park,I felt alone without any companions.Worse still,I had no money,so I had to walk home,covered as for as 5 kilometers.

假设你是李华，你班将于本周日去红枫湖游玩。请你根据以下信息给外教Tom写信，邀请他参加。

1.出发及返回时间；

2.活动：骑车，划船，烧烤等。

注意：

1.词数100左右；

2.可适当增加细节，以使行文连贯；

3.开头和结尾已给出，不计入总词数。

Dear Tom,

____________________________________________________________________________________________

_______________________________________________________________________

Yours,

Li Hua

Events at Brown

12:00 PM—1:00 PM,March 1,2017

"I had no ideal"—Export Control Brown Bag (4-part series)

Horace Mann House,Room 103,47-49 George Street

Brown's Office of Research Integrity (ORI) is hosting a 4-part Brown Bag series on “Export Controls at the University”.Export Controls are federal government laws and regulations.The series will explore when research activities fall under Export Control laws,why “fundamental research”is so important,and why traveling to sanctioned（被制裁的）or embargoed（被禁运的）countries,such as Iran or Cuba,still presents a lot of challenges.The first session,“I had no idea!”,will explore why export controls cannot be ignored at a university campus.

The sessions are open to the entire Brown community.Booking in advance is required: juliane_blyth@brown.edu

4:00 PM—5:00 PM,March 1,2017

JCB Weekly Afternoon Talk

John Carter Brown Library,Reading Room,94 George Street

Informal weekly afternoon presentation in the MacMillan Reading Room at the John Carter Brown Library (JCB).Fellows in Residence will give a talk on their current research project.Q & A session follows,along with a display of relevant items from our collection.All are invited to attend this free,weekly event.

6:30 PM—7:30 PM,March 1,2017

Brow Amateur Radio Club Meeting

Sayles Hall.Room 305,79-81 Waterman Street

The weekly meeting of the Brown Amateur Radio Club.All are welcome to attend and learn more about radio and join the club—no license required!

8:00 PM-9:00 PM,March 1,2017

Athletes in Action Prime Time Gathering

Pembroke Field House,449-451 Brook Street

Join your fellow Brown University athletes to learn more about faith,sport,and life.Through guest speakers, team building activities,and small group discussions,we explore the intersection（交集）of the spiritual and the physical in order to maximize our potential.

We meet every Thursday 8-9 pm in Pembroke Field House.There are new athletes that attend every week,and most likely you'll know a number of them already since there are many different teams represented.Hope to see you there!

1.Which event can be beneficial to those who do international research?

A. “I had no idea!”—Export Control Brown Bag

B. JCB Weekly Afternoon Talk

C. Brown Amateur Radio Club Meeting

D. Athletes in Action Prime Time Gathering

2.What will those who attend the JCB Weekly Afternoon Talk do?

A. Meet at Sayles Hall. B. Charge entrance fees.

C. Share their research. D. Collect relevant items.

3.What can you do in the Athletes in Action Prime Time Gathering?

A. Play basketball with new athletes. B. Discuss your potential.

C. Play games to develop teamwork. D. Watch new athletes play games.

4.Where would you be most likely to find the text?

A. In a travel guidance. B. On a university website.

C. In an academic magazine. D. In a local newspaper.

—Why did you go back to the library?

—Oh，I left my classmate Julia there.

A. to wait B. waited

C. waiting D. being waited

It was a match，with the winning goal scored in the final minute.

A. tight B. tough

C. rough D. tense

—Can you make sure ?

—Sorry, I can’t.

A. when will she arrive

B. whether she will join us or not

C. why she would speak in the meeting

假定英语课课上老师要求同桌之间交换修改作文，请你修改你同桌写的以下作文。文中共有10处语言错误，每句中最多有两处。错误涉及一个单词的增加、删除或修改。

增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（＼）划掉。

修改：在错的词下画一横线，并在该词下面写出修改后的词。

注意：1.每处错误及其修改均仅限一词。

2.只允许修改10处，多者（从第11处起）不计分。

My friend Lin Tao was born in Liaoning Province to the northeast of China. He met with a traffic accident when he was younger. As a result, he lost one of his legs. Although he suffered a great deal, he never loses his heart. Lin Tao has been published a book. He enjoys playing his guitar and listen to music. He does excellent job in school. But he is always ready to help those in trouble. He wins the respects of his classmates and his teachers.

In my opinion, Lin Tao is extreme brave and he sets a good example to we all.

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