A black hole is created when a large star burns out. Like our sun, stars are unbelievably hot furnaces(熔炉) 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 (处理) 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 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

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 (无忧无虑) 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

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(膨胀)."

       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(极大的幸福)."

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

阅读下列短文并按要求回答问题(共3小题,满分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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