A black hole is a place in space where gravity pulls so much that even light cannot get out. The gravity is so strong because matter has been squeezed into a tiny space. This can happen when a star is dying.
Because no light can get out, people can’t see black holes. Space telescopes with special tools can help find black holes. The special tools can see how stars that are very close to black holes act differently from other ones.
Black holes can be big or small. Scientists think the smallest black holes are as small as just one atom. These black holes are very tiny but have the mass of a large mountain. Mass is the amount of matter, or “staff”, in an object.
Another kind of black hole is called “stellar”(星球黑洞). Its mass can be up to 20 times more than the mass of the sun. There may be many stellar mass black holes in Earth’s galaxy. Earth’s galaxy is called the Milky Way.
The largest black holes are called “supermassive”(超大质量黑洞). These black holes have masses that are more than one million suns together. Scientists have found proof that every large galaxy contains a supermassive black hole at its center. The supermassive black hole at the center of the Milky Way galaxy has a mass equal to about four million suns and would fit inside a very large ball that could hold a few million Earths.
Scientists think the smallest black holes formed when the universe began. Stellar black holes are made when the center of a very big star falls in upon itself, or falls apart. When this happens, it exploded part of the star into space. Scientists think supermassive black holes were made at the same time as the galaxy they are in.
A black hole can not be seen because strong gravity pulls all of the light into the middle of the black hole. But scientists can see how the strong gravity affects the stars and gas around the black hole. Scientists can study stars to find out if they are flying around, or orbiting a black hole.
When a black hole and a star are close together, high-energy light is made. This kind of light cannot be seen with human eyes. Scientists use satellites and telescopes in space to see the high-energy light.The gravity of a black hole may become so strong that light cannot get out when ____________.
| A．the star is going to die |
| B．special tools are used on it |
| C．other stars come close to it |
| D．it is seen from the space telescopes |
According to the passage, which of the following is NOT true?
| A．A black hole can be very tiny but extremely heavy. |
| B．The gravity of a black hole holds all light in its center. |
| C．Scientists observe high-energy light through their own eyes. |
| D．Some small black holes came into being as early as the universe. |
Which can be inferred from the passage?
| A．Every galaxy must have a black hole. |
| B．A galaxy is the center of the universe. |
| C．A galaxy consists of a large group of stars and planets. |
| D．Earth’s galaxy is called the Milky Way. |
What does the last sentence in Paragraph 5 suggest?
| A．Neither the sun nor the earth is as heavy as a black hole. |
| B．There is only one supermassive black hole at the center of the Milky Way. |
| C．The supermassive black hole had existed before the Milky Way was formed. |
| D．There is a reason why the large black holes are called “supermassive”. |
The last two paragraph mainly focus on the question of _________.
| A．what a black hole is |
| B．how black holes form |
| C．how big black holes are |
| D．how scientists know about black holes |
It was 8:35 am. My girls and I were rushing through the front door of the school as I yelled, “Hurry up! The bell was about to…” RIIIIIIIING! The girls froze and their eyes widened. My shoulders sagged(下垂). We were too late.
We were often late for school last year, and every time we ran breathlessly into the attendance I heard myself making silly excuses to Beth, the long-suffering secretary: our alarm didn’t go off; there was so much traffic; it was my husband’s fault; the dog…I didn’t know-something about the dog!
As time passed by, my lying became a habit, and it raised a red flag for me. Lying - even in the form of “harmless” excuses - means we’re ashamed. Shame is different from guilt. Healthy guilt is fair and helpful. But shame can be dangerous. Nothing ruins the connection between two people more quickly than shame and lies do. Anyone trying to live a healthy and honest life must avoid shame at any cost. I was trying to live a healthy and honest life, but my excuses were keeping me from reaching my goal. So I vowed（发誓）to do something different .
The next time we were late, I went to the attendance office. When Beth asked me to fill in a form with the reason for being late, I told the truth. “These days, we are very tired and disorganized,” I wrote. Beth looked down at that form, and the slowly looked up at me. She gave us a warm and big smile and her blue eyes twinkled. She started laughing. So did my kids and I.
We’re all imperfect human beings. We make mistakes. Everyone does make mistakes. However, it’s OK to tell the truth about them. It’s OK to forgive ourselves and promise to try again.By writing Paragraph1, the author wants to show that .
| A．her daughters were not easy to deal with |
| B．she didn’t have an organized lifestyle |
| C．her daughters didn’t like going to school |
| D．she lived a lazy life with her daughters |
What do we know about the author from Paragraph2?
| A．She lived an extremely busy life. |
| B．She liked complaining about life. |
| C．She liked making fun of other people. |
| D．She liked making excuses for her lateness. |
We learn that as time went by, the author .
| A．found that other people liked lying to her |
| B．realized the harm of lying and wanted to change |
| C．found that shame had a positive effect on her life |
| D．realized that she could no longer live a healthy life |
The last paragraph shows when we make a mistake we should .
| A．blame it on different things |
| B．never let others know it is our fault |
| C．never forgive ourselves for making it |
| D．forgive ourselves and try harder next time |
As weather cools across the United States, a growing number of Americans visit farms. They harvest fruits, enjoy hay wagon rides and walk in the fields. These people are called “agri-tourists.” They improve the economy of rural areas and help farmers increase their profits.
School children are walking in a corn field maze. The corn is cut into tricky passageways that make it difficult to find a way out. The children are from Yorktown Elementary School in Bowie Maryland. They have traveled to Montpelier Farms in Prince George’s County which is also in Maryland. The farm is about 40 kilometers from The White House.
Debbie Pierson is the student’s teacher. “We go on these kind of field trips so that the children will have a hands-on experience of what it’s like to be on a farm,” Pierson said.
In Loudoun County Virginia, there are farms where grapes are grown for use in making wine. Many of the farms let people visit, and drink the wine that is made there. Bill Hatch owns the Zephaniah Farm Vineyard. He holds wine tastings in his home. “We are doubling the number of visitors to our farm every year. We have an average of 250 people on a weekend,” Hatch said.
As more people visit farms, more farmers are adding activities in which visitors can take part.
Malcolm Baldwin owns WeatherLea Farm and Vineyard in Loudoun County. Six years ago, he began letting people be married at his farm. They can also sleep at the farm overnight. Mr. Baldwin says the money he makes from these activities let him keep his small farm operating. “But without the animals, and without the vines, the wedding business wouldn’t be as profitable (有利可图的), because people like to see the vines. They like to see the animals and without which I don’t think this will be a popular place,” Baldwin said.We can infer from the first paragraph that people always go for field trips in _______.
| A．Spring | B．Summer | C．Autumn | D．Winter |
The underlined word “maze” in the passage is similar to “_______”.
| A．puzzle | B．trip | C．house | D．activity |
On Malcolm Baldwin’s farms, visitors can ________.
| A．taste the wine made in the USA |
| B．raise and hunt animals |
| C．do wedding business |
| D．have fun as well as bring him money |
Every month, Julia and her cousins would go to visit their grandparents. They would be excited because their grandfather would give them a few coins. Then they would buy toys or sweets. The grandparents commented that, behaving like this, the children would never learn to manage their money. So they planned a special test, in which the children would have to show, over the course of a year, just what they could manage to get with those few coins.
Some thought that they would save their money, but Ruben and Nico continued spending it all on sweets. So they give up saving.
Monty decided to manage his money by exchanging it: buying and selling things, or betting (打赌) it with others. Soon he surprised the whole family. He had accumulated (积聚) lots of money. However, Monty was not very careful, and he got involved in more and more risky deals. A few months later he became penniless after a losing bet. Alex, had a will of iron. He saved the money and at the end of the year he had collected more money than anyone. Even better, with so much money, he managed to buy sweets at a reduced price, so that on the day of the competition he was presented with enough sweets for much more than a year. And even then, he still had enough left over for a toy. He was the clear winner, and other children learned the advantages of knowing how to save and how to wait.
There was also Julia. Poor Julia didn’t enjoy the competition, because even though she had had a wonderful secret plan, she had spent her money without giving her plan enough time to work. However, she was so sure that her plan was a good one, that she decided to carry on with it, and maybe change the expressions on her relatives’ faces, who had seemed to be saying “What a poor girl shel is. She couldn’t manage to save anything”.
When she was about to complete the second year of her plan, Julia surprised everyone by turning up at the grandparents’ house with a violin and a lot of money. She did it really well.Who saved nothing at the end of the first year?
| A．Ruben, Julia and Alex | B．Ruben, Nico and Monty |
| C．Ruben, Monty and Julia | D．Ruben, Nico and Alex |
Why did the grandparents plan a test on the children?
| A．Because they wanted the children to learn to spend money. |
| B．Because they wanted the children to learn to save money. |
| C．Because they wanted the children to learn to manage money. |
| D．Because they didn’t want the children to buy toys and sweets any more. |
From Monty’s story, the children learned ______________________.
| A．to save and to wait. |
| B．to buy and to sell things |
| C．to set a achievable goal. |
| D．to be careful and self-disciplined |
The underlined sentence in the fourth paragraph means ______________.
| A．Julia will bring disasters to herself and her family. |
| B．Julia is not good at managing money. |
| C．Julia is too stupid to do anything well. |
| D．Julia has so many secrets that nobody likes her. |
Our society reports many negative messages about bicycling in traffic. Bicycling in traffic is considered by many to be reckless and sometimes rude. The most common advice given to cyclists is to avoid busy roads that provide convenient access to important places, which means they should only go to unpopular destinations on undesirable and inconvenient roads. Another popular idea is that cyclists should stay as close to the edge of the road as possible in order to stay out of the way of cars. Getting in the way of cars is considered to be an invitation to death, because car drivers are often expected to run into anything that is slower or more vulnerable. Going together with motor traffic used to be regarded as a nice idea for cyclists, but today it is thought to be suicide. Roads are believed to be designed for cars and not for bicycles. Inferior bicycles may hold that they have the right to use the road, but they had better stay out of the way of superior users or they will be “dead right”.
As a result of these “common-sense” beliefs, bike safety programs developed by motoring organizations and “pedestrian-style” cyclists during the 20th century attempted to teach cyclists to provide a clear path to motorists at all times by hugging the edge of the road, riding on sidewalks so cyclists can see when to get out of the way. Some towns tried to prohibit bicyclists from operating on important roads or roads without shoulders. Engineering projects designed for bicycle safety have involved construction of side paths to get cyclists off roads and bike lanes to keep cyclists out of the way of motorists. The benefit of these efforts is to protect cyclists from collisions from behind, which are widely believed to be the greatest danger to cyclists and caused by cyclists’ failure to keep up with the desired speed of motor traffic. This is the taboo that harms the bicycle transportation policy: that bicyclists must be kept out of the paths of motorists or they will surely be killed.According to the author, bicycling should be ________.
| A．supported | B．banned |
| C．controlled | D．cancelled |
From the first paragraph, the person riding a bicycle in the city should take ________.
| A．main roads | B．streets |
| C．highways | D．sidewalks |
Why do many people do not agree that people should ride bicycles on roads?
| A．Most people think roads are designed for cars not for cyclists. |
| B．People riding bicycles are considered to be inferior. |
| C．People’s riding on the road is against the law of the country. |
| D．People riding bicycles are not experienced. |
The underlined phrase “cyclists’ failure to keep up with the desired speed of motor traffic” in the second paragraph means ________.
| A．cyclists’ speed is beyond the limit |
| B．cyclists’ speed is much lower than that of motorists |
| C．cyclists often compete with motorists on the roads |
| D．motorists usually look down upon cyclists |
What does “superior users” in paragraph one refer to?
| A．Bicyclists. | B．Government leaders. |
| C．Motorists. | D．Pedestrians. |
In earliest times, men considered lightning to be one of the great mysteries of nature. Some ancient peoples believed that lightning and thunder were the weapons of the gods.
In reality, lightning is a flow of electricity formed high above the earth. A single flash of lightning 1.6 kilometres long has enough electricity to light one million light bulbs.
The American scientist and statesman, Benjamin Franklin, was the first to show the connection between electricity and lightning in 1752. In the same year he also built the first lightning rod (避雷针). This device protects buildings from being damaged by lightning.
Modern science has discovered that one stroke of lightning has a voltage (电压) of more than 15 million volts. A flash of lightning between a cloud and the earth may be as long as 13 kilometers, and travel at a speed of 30 million meters per second.
Scientists judge that there are about 2,000 million flashes of lightning per year. Lightning hits the Empire State Building in New York City 30 to 48 times a year. In the United States alone it kills an average of one person every day.
The safest place to be in case of an electrical storm is in a closed car. Outside, one should go to low ground and not get under a tree. Also, one should stay out of water and away from metal fences. Inside a house, people should avoid open doorways and windows and not touch wires or metal things.
With lightning, it is better to be safe than sorry.People once thought lightning came from ________.
| A．the sky | B．the gods |
| C．the earth | D．nature |
According to the passage what do you think all buildings need?
| A．Metal fences. | B．Electricity. |
| C．lightning rods. | D．Machines. |
Lightning can travel ________.
| A．as quickly as water |
| B．not so quickly as electricity |
| C．at very low speed |
| D．at very high speed |
Which of the following is NOT true?
| A．In the U.S. about 360 people die from lightning in a year. |
| B．The Empire State Building frequently gets hit by lightning. |
| C．Swimming during a thunder storm is a good idea. |
| D．A closed car is the best place to be during an electrical storm. |
Lightning is probably ______ to man.
| A．useful | B．kind | C．useless | D．Friendly |
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