Cable TV began in 1948 in the USA, but it took 50 years________ 66 percent of American households had it.
A. before B. after C unless D. since
高二英语单项填空中等难度题
Cable TV began in 1948 in the USA, but it took 50 years ________ 66 percent of American households
had it.
A.before | B.when | C.after | D.until |
高二英语单项填空简单题查看答案及解析
Cable TV began in 1948 in the USA, but it took 50 years________ 66 percent of American households had it.
A. before B. after C unless D. since
高二英语单项填空中等难度题查看答案及解析
Cable TV began in 1948 in the USA, but it took 50 years ________ 66 percent of American households had it.
A.before B.when
C.after D.until
高二英语单项填空简单题查看答案及解析
The river ________ at least 50 meters in width, but the ten-year-old boy can swim across it within minutes.
A.is measured B.measures
C.is measuring D.is being measured
高二英语单项填空中等难度题查看答案及解析
The river ________ at least 50 meters in width, but the ten-year-old boy can swim across it within minutes.
A. is measured B. measures
C. is measuring D. is being measured
高二英语单项填空中等难度题查看答案及解析
It took 100 years, but finally, scientists, from CalTech, MIT and the LIGO Scientific Collaboration, proved Albert Einstein's theory that gravitational(引力的) waves exist. The waves were predicted as part of Einstein's General Theory of Relativity nearly 100 years ago. It was the theory of the physics behind the workings of our world and the universe. The idea was that the waves are like ripples in space, caused by some of the violent and energetic processes in the Universe. For example, two black holes crashing into each other.
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 or waves. Space time is like the surface of the water. So that means gravitational waves are like the ripples moving out from where the rock hits the water. It might be hard to understand, but those gravitational waves expand and contract space and time as they move through space. And when they get to the Earth, the waves pass through, and contract and expand the planet as the wave goes by.
It was Einstein who said these gravitational waves should be observable. But these are not huge waves. They are very, very small, which is why it took so long to find them. You cannot see them with your eyes. They are smaller than the size of an atom.
How did the scientists find them? For years, scientists have been watching two black holes in another galaxy faraway with the help of the Laser Interferometer Gravitational-Wave Observatory. The two were spinning around each other, moving closer and closer together. When they finally crashed into each other, it was with such power and force, that gravitational waves 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. They are the same waves that the scientists announced this past week.
The National Science Foundation tweeted that each of the black holes was thought to be 29 to 36 times the mass of our sun. So, what does this discovery mean? Abhay Ashtekar, a Penn State physicist, who was not on the discovery team, said: "Our understanding of the heavens changed dramatically."
1.According to the 1st paragraph, we can learn that_______.
A. gravitational waves were part of Einstein's General Theory of Relativity
B. scientists proved that gravitational waves existed 100 years ago
C. gravitational waves were the theory of the physics behind the universe
D. gravitational waves result from two black holes crashing into each other
2.From the passage we can know that the gravitational waves______.
A. are not supposed to be observed.
B. are very huge.
C. are easy to be found.
D. can’t be seen with our eyes.
3.Why did scientists spend years watching two black holes?
A. Because they wanted to see how the two black holes crashed into each other.
B. Because they wanted to find the gravitational waves.
C. Because they wanted to see the gravitational waves reach the Earth.
D. Because they wanted to know how black holes formed.
4.What can we infer from the passage?
A. The discovery has no relation to Albert Einstein's theory
B. Throwing a rock into a pond can generate gravitational waves
C. The discovery will considerably affect people’s understanding of universe
D. gravitational waves can’t contract and expand the Earth
高二英语阅读理解困难题查看答案及解析
课文填空(每空至多三个词)
California is the third largest state in the USA but has the largest population. It also has the1. of being the most multicultural state in the USA, 2. people from all over the world. The customs and languages of the immigrants live on in their new home. This diversity of culture is not 3. when you know the history of California.
People from different parts of the world, attracted by the climate and the lifestyle, still immigrate to California. It is believed that before long the mix of nationalities will be 4. great that there will be no distinct major 5. or cultural groups, but simply a mixture of many races and cultures.
Although at present human egg cells and embryos 6. for cloning research are difficult to obtain, newspapers wrote of evil leaders 7. to clone themselves to attain their ambitions. Religious leaders also raised moral questions. Governments became nervous and more conservative. Some began to reform their legal systems and 8. research into human cloning, but other countries like China and the UK, continued to accumulate evidence of the 9. medical aid that cloning could provide. However, scientists still wonder whether cloning will help or harm us and 10. it is leading us.
高二英语语法填空中等难度题查看答案及解析
It was not until the end of last year _____ the economy in our country began to develop rapidly.
A.when B.that C.which D.in which
高二英语单项填空简单题查看答案及解析
LEGO began as one man’s small business. But today, it is the second largest toy company in the world. The LEGO company sells small, brightly colored plastic bricks (积木). People can buy LEGO bricks in over 90 countries.
Ole Kirk Kristiansen from Denmark began his own business in 1932. He made products (产品) from wood including colorful wooden toys. Kristiansen’s young son, Godtfred, worked with him. Their business helped them make a lot of money.
By 1934, the Kristiansens named their company LEGO, which came from two Danish words, “leg” and “godt”, meaning “play well”. The LEGO company grew slowly. But it continued to create excellent wooden toys.
By 1947, the LEGO company began using a new material (材料) to make their toys — plastic. One of the toys they sold was called the Automatic Binding Brick. A person could put the bricks together to build something. But the bricks did not hold together easily. Still, they were a popular toy.
A few years later, in 1954, Godtfred Kirk Kristiansen had a big idea. He wanted all of the LEGO bricks to fit together. Finally, four years later, in 1958, the LEGO company found their answer. They invented the first modern style LEGO brick, which was similar to the Automatic Binding Brick but each piece would fit with any other piece.
Since that time, any toy that the LEGO company created would fit with any other toy they created. Today, LEGO is not only the second largest toy maker in the world, but also making its products a great way for children to learn creative building skills.
1.When the LEGO company was set up, it ________.
A.had a rapid growth B.failed to attract children
C.invited children to work with it D.was small but successful
2.What do we know about the Automatic Binding Brick?
A.It was liked by few people. B.It was the best of its kind.
C.It was a building toy. D.It was made of wood.
3.The first modern style LEGO brick________.
A.fit together perfectly
B.was created by Godtfred and his father
C.was invented in the early 1950s
D.differed greatly from the Automatic Binding Brick
4.What’s the best title for the text?
A.LEGO: Educational Toys
B.LEGO: Play Well
C.Toy Companies: From Small to Big
D.Toy Companies: Never Too Late to Create
高二英语阅读理解中等难度题查看答案及解析
I began cycling in 2004 when I was a poor student. It was dangerous, sure, but cycling is the fastest, cheapest point-to-point form of transport in Melbourne. I own a car now, but that’s just for transporting the baby or groceries.
I hate driving. So it’s been quite encouraging watching the growth in cyclist numbers over the past decade. It is said that over 10,000 cyclists enter the CBD (Central Business District) each day, taking pressure off public transport. But as more people take to cycling as a way of transport, the number of cyclists seriously injured or killed keeps increasing. And that is a sign that our infrastructure (基础设施) is still not good enough.
Melbourne was once a dream for cyclists--flat, long, wide roads, with plenty of paths along rivers. Now, cycling can be deadly, with roads taken up by cars. I have a friend who broke her back and was lucky to escape death and others with broken bones. In my time riding, I’ve been forced off the road by a truck, cut off by four-wheel drives, and told to get off the road. Drivers are a particularly rude to cyclists. And that’s a sign of exactly one thing: inadequate infrastructure.
We shouldn’t need to be taught how to coexist in the same narrow space. Drivers and cyclists should be kept apart. Designing bike paths so riders are channelled between moving cars and parked cars is deadly. All it takes is one daydreaming driver to fling open the door and you are gone. That’s what happened to the young university student James.
This year, there are to be new cycling lanes (车道) built on Glen Road, where James died in 2010. But these lanes are not safe. Cyclists must still pass between two rows of cars.
1.What does the underlined word “that” in Paragraph 2 refer to?
A. Some people hating driving.
B. More cyclists having accidents.
C. More people choosing to cycle.
D. Distracted driving happening a lot.
2.What is the main idea of Paragraph 3?
A. Many people are bad at cycling.
B. There are many cars in Melbourne.
C. It’s dangerous to cycle in Melbourne.
D. Melbourne was once very beautiful.
3.Which was the major cause of James’ death according to the author?
A. Cross’ carelessness.
B. A driver’s mistake.
C. Unsafe bike paths.
D. An outdated legal system.
4.What is the purpose of the text?
A. To stress the necessity of safe bike paths.
B. To encourage readers to cycle.
C. To criticize rude driving behavior.
D. To tell a personal story.
高二英语阅读理解中等难度题查看答案及解析