科目: 來(lái)源: 題型:閱讀理解
A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces(熔爐) that burn their own matter as fuel. When most of the fuel is used up, the star begins to die.
The death of a star is not a quiet event. First there is a huge explosion. As its outer layer is blasted off into space, the dying star shines as brightly as a billion suns.
After the explosion gravity pulls in what’s left of the star. As the outside of the star sinks toward the center, the star gets smaller and smaller. The material the star is made of becomes tightly packed together. A star is so dense that a teaspoon of matter from it weighs billion of pounds.
The more the star shrinks, the stronger the gravity inside it becomes. Soon the star is very tiny, and the gravity pulling it in is unbelievably strong. In fact, the gravity is so strong that it even pulls light into the star! Since all the light is pulled in, none can go out. The star becomes black when there is no light. Then a black hole is born!
That’s what we know about black holes. What we don’t know is this: What happens inside a black hole after the star has been squeezed into a tiny ball? Does it keep getting smaller and smaller forever? Such a possibility is hard to imagine.
But if the black hole doesn’t keep shrinking, what happens to it? Some scientists think black holes are like doorways to another world.They say that as the star disappears from our universe, it goes into another universe. In other words a black hole in our universe could turn into a “white hole” in a different universe. As the black hole swallows light, the white hole shines brightly — somewhere else. But where? A different place, perhaps, or a different time — many years in the past or future.
Could you travel through a black hole? Right now, no. Nothing we know of could go into a black hole without being crushed.So far the time being, black hole must remain a mystery.
Black holes are a mystery—but that hasn’t stopped scientists from dreaming about them. One scientist suggested that in the future we might make use of the power of black holes. They would supply all of Earth’s energy needs, with plenty to spare. Another scientist wondered if a black hole could some day be used to swallow earthly waste—a sort of huge waste disposal (處理) in the sky!
When the star begins to die ______.
A.there is no fuel left in it B.its outer layer goes into space first
C.a(chǎn) huge explosion will happen D.it doesn’t give off light any longer
Which of the following doesn’t help produce a black hole?
A.The gravity inside the star is very strong.
B.The light can’t go out of the star.
C.The star becomes smaller and smaller
D.The dying star shines very brightly.
The black hole ______.
A.continues becoming smaller and smaller all the time
B.goes into another universe and becomes a white hole
C.can pull in everything we know of in the world
D.will appear at another place at a different time
The author mainly intended to tell us _____.
A.A New Scientific Discovery: Black Holes
B.How Black Holes Came Into Being
C.What Black Holes Are
D.Travel Through A Black Hole
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科目: 來(lái)源: 題型:
以中學(xué)生的名義寫(xiě)一篇100詞左右的文章呼吁世界各地的中學(xué)生加入到拯救大熊貓(the giant panda)的行列中來(lái)。要求用到提示內(nèi)容,行文連貫、流暢、完整。內(nèi)容包括:1. 大熊貓是中國(guó)的稀有動(dòng)物,也是世界的稀有動(dòng)物之一,為中國(guó)人民
和世界人民所喜愛(ài);
2. 大熊貓生長(zhǎng)在山里,以竹子為食,由于山林遭到破壞,竹子被砍伐,大熊貓覓食越來(lái)越困難,正瀕臨滅絕;
3. 我國(guó)已建立數(shù)個(gè)自然保護(hù)區(qū)來(lái)保護(hù)大熊貓,但需要更多的資金;
4. 我們希望大家伸出援助之手來(lái)保護(hù)大熊貓。
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科目: 來(lái)源: 題型:
How often do you visit your grandparents?
A. Every other week. B. Two weeks. C. For two weeks. D. For a few weeks.
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科目: 來(lái)源: 題型:
Her excellent performance in the competition proved that she was a winner.
A.value B.worthy C.worth D.worthwhile
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科目: 來(lái)源: 題型:
Nobody noticed the thief enter the house because the lights happened to _______.
A. go over B. go through C. go on D. go out
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科目: 來(lái)源: 題型:閱讀理解
The other day, I happened to meet someone I hadn’t seen for many years. I couldn’t believe the change in him. In fact, he didn’t even seem like the 36 person.
When I first knew Bill, back in 37 , he was one of the most carefree (無(wú)憂無(wú)慮) people I had ever 38 . He was always ready to have a party. He thought 39 of going out for beer at three o’clock in the morning or driving 50 miles to see an old 40 he really liked. Bill and I were in the same class in college, and 41 was never dull when he was 42 . With him there was one wild 43 after another. Sometimes I wonder how we 44 to study for our exams.
Last week I was in <<Houston>> on business and I ran into Bill in the bar at the hotel. 45 , I wasn’t even sure it was 46 . Was this short-haired businessman really the same person? I wasn’t really sure until I came near him but it indeed was Bill. Now he works for a bank. He 47 most of the evening about his job, his new car and his house. How he had changed! Back when we were in college, the 48 thing Bill cared about was possessions. Now they seemed to be his main 49 . Although I have changed quite a bit myself, somehow, I never 50 Bill changing so much. My image of him 51 the one I had formed 52 the time when we were college students together.
I suppose it’s 53 to expect people to remain the same, especially 54 I have changed so much myself. But I must say that I enjoyed the old Bill much more than the new Bill. Maybe he 55 the same way about me.
A. proper B. same C. usual D. right
A. childhood B. the army C. his thirties D. college
A. considered B. supposed C. met D. expected
A. nothing B. much C. most D. none
A. man B. hospital C. movie D. country
A. learning B. life C. work D. fun
A. in B. out C. away D. around
A. adventure B. mistake C. chance D. joke
A. decided B. intended C. managed D. hoped
A. First of all B. At first C. Now and then D. All the time
A. that B. us C. there D. him
A. thought B. talked C. argued D. spent
A. first B. last C. next D. only
A. interest B. event C. subject D. problem
A. forgot B. minded C. liked D. imagined
A. remained B. reminded C. suggested D. became
A. since B. from C. at D. till
A. unnecessary B. foolish C. common D. unusually
A. because B. that C. how D. when
A. felt B. acted C. looked D. discovered
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科目: 來(lái)源: 題型:閱讀理解
The findings of a new survey have American professors talking about the good old days—when A's were a lot tougher to earn.
Sites like Rate My Professors.com make it easy for students to find a class taught by a professor who is known as an "easy grader".A recent survey by Kaplan Test Prep found that 46 percent of the more than 1,200 students polled admitted to using the site for just such a purpose.
"Our research shows that many of today's college students are looking at multiple factors when picking out courses: overall teacher quality that will result in a good learning experience, but also instructors who don't like to award a lot of C's and D's," said Jeff Olson, vice president of research at Kaplan Test Prep.
"While it makes sense that students would choose kinder graders, it also helps explain the recent popularity of grade inflation(膨脹)."
Grade inflation is seen by many professors as poisoning the learning environment.Some, like former Duke University professor Stuart Rojstaczer, are righting it head-on.
On his website, Gradelnflation.com, he releases an annual list of schools where grade inflation is the worst.
This year, he decided to name the schools where grades were inflated the least.He praised, for example, Princeton University, as well as Purdue University, where the average GPA has remained around 2.8 for over 30 years.
"Purdue doesn't even seem to know that grade inflation exists in the US," Rojstaczer says."Ignorance is bliss(極大的幸福)."
Grade inflation is spreading because _____.
A.it's poisoning the learning environment
B.instructors intend to improve their overall teaching quality
C.many instructors adapt to the students' expectations
D.students get easy access to sites like RateMyProfessors.com
The passage suggests that _____.
A.universities will employ hard graders
B.if we want to be happy, we should be ignorant
C.A's are becoming easy to earn at most US universities
D.professors and instructors should give students higher grades
The writer tends to _____.
A.favor easy graders B.see grade inflation as unavoidable
C.oppose Kaplan Test Prep D.miss the days when A's were hard to earn
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科目: 來(lái)源: 題型:閱讀理解
閱讀下列短文并按要求回答問(wèn)題(共3小題,滿分7分)
In China, more and more middle school students are getting shorter sleeping time than before. Most students sleep less than nine hours every night, because they have much homework to do. Some homework is given by their teachers, and some by their parents. Also, some students don’t know how to save time. They are not careful enough while they do their homework, so it takes them a lot of time. Some students spend too much time watching TV or playing computer games. They stay up(熬夜) very late. Some students have to get up early every morning on weekdays to get to school on time by bus or by bike. It can be a long way from home to school. It will probably make them sleepy(困的) during school hours.
Schools and parents should cut down some of the homework so that our children can enjoy more than nine hours of sleep every night for their health. For children, they should make the most (best use ) of their time. When they have enough time for sleeping , they will find it much better for both their study and health.
According to the passage, who else gives children some homework to do besides their teachers? (no more than 2 words)
________________________________________________________________
How many hours of sleep is good for students’ health? (no more than 4 words)
_____________________________________________________________
What is most likely to happen to a student who often goes to bed late and gets up early? (no more than 7 words)
______________________________________________________________
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科目: 來(lái)源: 題型:
書(shū)面表達(dá)
假如你叫李明。你的好友Mark生病了,在家復(fù)習(xí)迎考。以下是學(xué)校關(guān)于英語(yǔ)期末考試的說(shuō)明。請(qǐng)根據(jù)該通知寫(xiě)一封信給Mark,詢問(wèn)病情并告訴他考試的有關(guān)事宜。
期末考試時(shí)間:下周四上午8:00—10:00。 復(fù)習(xí)建議:掌握本學(xué)期所學(xué)的重要單詞、短語(yǔ)及句型; 看筆記及平時(shí)的練習(xí); 考前練習(xí)寫(xiě)幾篇120字左右的作文。 如有疑難問(wèn)題,請(qǐng)隨時(shí)和老師或同學(xué)聯(lián)系 |
注意:1、短文必須包括所有要點(diǎn),可適當(dāng)發(fā)揮;
2、字?jǐn)?shù):120詞左右;
3、短文的開(kāi)頭與結(jié)尾已給出;
4、提示:短語(yǔ):phrase 句型:sentence pattern
平時(shí)的練習(xí):daily exercises 作文:composition
Dear Mark,
Sorry for your illness. Are you feeling any better now?
__________________________________________________________________________________________________________________________________________
Hope you will recover soon and also get a satisfactory mark in the exam.
Yours truly,
Li Ming
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科目: 來(lái)源: 題型:
--- It’s been a wonderful party. Thank you very much.
--- __________.
A. I’m glad you enjoy it B. No, thanks
C. It’s OK D. With pleasure
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