A policeman moved along the street. Near the ...

The Mystery of Dark Matter

If you look at the night sky, you'll often see stars moving very quickly. In fact, they move much more quickly than they should according to their size and the laws of physics. Scientists do not completely understand why the speed of these stars is so high. But many believe the reason is that much of the universe is made up of something called "dark matter". Groups of stars called galaxies, such as the Milky Way, might even consist of ninety per cent dark matter.

How much something weighs depends on where it is. The same object weighs only half as much on Mars as it does on Earth and almost three times as much on Jupiter. So scientists prefer to talk about the mass of something rather than how much it weighs, because mass does not change. They can work out the mass of galaxies by measuring the distance between them and the speed they move.　 Recently, Dr. Jorge Penarrubia and a team from Edinburgh University discovered something interesting. The mass of the Milky Way is only half as much as the mass of another nearby galaxy, Andromeda. This seems strange, but dark matter may explain why.

Finding out more about dark matter could help us understand how the universe began, but this is not easy. Lots of scientists with different types of expert knowledge are working on the problem. The Edinburgh team is working with many other universities like the University of British Columbia.

We can't see dark matter, it's very difficult to measure and we can't find out its mass. Unlike stars, dark matter doesn't produce or reflect light. But we can make a good guess that it is there because of the way things move and the way light bends. Experts now think dark mater may be very different from the mater which we find on Earth. There may also be five times as much dark matter in the universe as ordinary matter.

The Swiss scientist Fritz Zwicky first gave dark matter its name in the nineteen-thirties. Researchers have been looking for it ever since.　 Today, technology such as the Large Hadron Collider is collecting more and more information but this technology cannot tell us everything.　 New ways of finding dark matter will be needed.　 Investigating dark matter may even mean we will need to start asking questions about the way we look at the universe, including the ideas of Albert Einstein.

1.In what way do scientists find out the mass of galaxies？

A.Depending on where they are.

B.Depending on how much they weigh.

C.According to the way they move and the laws of physics.

D.By calculating how far between them and how fast they move.

2.Which of the following statements about dark matter is NOT TRUE？

A.It can't be seen.

B.It doesn't reflect light.

C.It is not unlike ordinary matter.

D.It affects the movement of things.

3.What may get researchers looking for dark matter？

A.To change the way light bends.

B.To prove the ideas of Albert Einstein.

C.To collect more and more information.

D.To help understand the origin of the universe.

4.How is the article organized？

(P: Paragraph)

A. B.

C. D.

5.Which heading best matches Paragraph 5?

A.It's there but we can't see it.

B.Sharing ideas leads to success.

C.We may need to change the way we think.

D.What your eyes can see can't be fully explained,

高一英语阅读理解困难题查看答案及解析

There was once a young shepherd boy who tended his sheep at the foot of a mountain near a dark forest. It was lonely and　　　 1.　　 (bore) for him watching the sheep all day.

No one was near　　 2.　　 there farmers he could sometimes see working in the fields in the valley below.

One day the boy thought of a plan by　　 3.　 he could get a little company and have some fun. He ran down toward the valley　　 4.　　 (cry), “Wolf! Wolf!”

The men ran to meet him, and　　 5.　　 they found out there was no wolf at all, they complained and returned to their work. However, the boy was very happy when he saw the men come running.

The boy enjoyed the company so much that a few days later he tried 6.　　 same trick again, and again the men ran to help him.

A few days later, a real wolf came from the forest and was heading　 7.　　 the sheep.

The boy ran toward the valley, and more loudly　 8.　 ever he cried,“Wolf! Wolf! A wolf has really appeared. ”

But the men, who had been　 9.　　 (fool) twice before, thought that he was tricking them again. No one came　　 10.　 (help) the boy. The lying shepherd boy was eaten up by the wolf with all his　 sheep.

高一英语语法填空中等难度题查看答案及解析

Along the either side of the street _______ two lines of trees.

高一英语单项填空简单题查看答案及解析

Along the either side of the street _______ two lines of trees.

A. has        B. have         C. is         D. are

高一英语单项填空中等难度题查看答案及解析

At the age of fourteen , Betty went to a _____ girls’ school along with her sister .

A.     Near    B. nearby   C. close   D. neighbor

高一英语单项填空简单题查看答案及解析

The story of how I got my job was a funny one.One day, I was _____ along a street to the interview ______ a yellow car suddenly cut in front of me ____ another car coming in the other _______,I had to brake hard and ______ another cyclist. We both fell,but ______ neither of us was hurt.I became angry and cycled as fast as possible to the driver of the yellow car to tell him______considered him. I told him what a bad______ I thought he was and he was a(n)_______ to other people on the road. His face turned _______.I warned him not to drive ________in the future so that everyone else could enjoy a long　 life.

I was in time for the ________. Having walked into the room, to my ___________,I found one of the three interviewers ___________ to be the driver of the yellow car. We looked at each other for a while,_______ silent.Then I decided to look_________ the whole matter as a great joke! I laughed and told him that I talked ________ the last time we met and this time it was turn for him to talk a great deal. Lost in thought for a while,he ________that I was not going to say anything about his bad driving. The interview went ________ .Two days later, I received a letter offering me the job.I was pleased that the manager----the driver of the yellow car, didn't ________ my rudeness to him.Through the experience, I find something that seems impossible at first sometimes turns out to be good.

1.A. cycling　　 B. walking　　 C. running　　 D. driving

2.A. then　　 B. when　　 C. while　　 D. as

3.A. as　　 B. for　　 C. with　　 D. by

4.A. condition　　 B. position　　 C. location　　 D. direction

5.A. knocked　　 B. bumped　　 C. beat　　 D. rushed

6.A. happily　　 B. unfortunately　　 C. luckily　　 D. disappointedly

7.A. which　　 B. that　　 C. what　　 D. how

8.A. driver　　 B. worker　　 C. cyclist　　 D. boss

9.A. pity　　 B. idiot　　 C. risk　　 D. fool

10.A. black　　 B. white　　 C. pale　　 D. red

11.A. carelessly　　 B. carefully　　 C. slowly　　 D. patiently

12.A. job　　 B. interview　　 C. meeting　　 D. appointment

13.A. excitement　　 B. joy　　 C. anger　　 D. astonishment

14.A. happened　　 B. wanted　　 C. seemed　　 D. planned

15.A. making　　 B. keeping　　 C. breaking　　 D. stopping

16.A. up　　 B. at　　 C. on　　 D. into

17.A. much　　 B. little　　 C. more　　 D. less

18.A. hoped　　 B. found　　 C. heard　　 D. wished

19.A. fast　　 B. terribly　　 C. well　　 D. slowly

20.A. realize　　 B. want　　 C. know　　 D. mind

高一英语七选五中等难度题查看答案及解析

While ___ along the street, I met an old friend of mine.

高一英语单项填空中等难度题查看答案及解析

The policeman came up to the house, whose door was open, _____ there for a while, and went in.

A．to stand           B．standing           C．stood             D．stand

高一英语单项填空中等难度题查看答案及解析

单词填空

1.Frightened, she didn’t dare to ____ (靠近) the front door in the dark.

2.The drowned boy had stopped ____ (呼吸) before he was saved.

3.After the interview, John came to the c____ that she was not fit for the job.

4.They were ____ (焦急地) waiting for the result when the telephone rang.

5.I feel honored to be one of the ____ (参与者) of the project.

6.Young people should become more ____ (独立的) of their parents.

7.Radio systems enable us to c____ each other even though we do not have a telephone within easy reach.

8.Many children are so ____ (上瘾的) to the Internet games that their studies are badly affected.

9.Our bodies are strengthened by taking exercise. S____, our minds are developed by learning.

10.There is nothing like a holiday to make us feel ____ (放松的).

高一英语单词拼写简单题查看答案及解析

In the quiet darkness, I could hear someone _______ the door and go upstairs.

高一英语单项填空简单题查看答案及解析