【正文】 of the following statements is NOT a fact? A. Black holes are dead stars. B. There is nothing as mysterious as a black hole. C. Black holes are invisible. D. Black holes have gravity. of the following is NOT a feature of a black dwarf? A. It is usually bigger than a white dwarf. B. It is dark. C. It is smaller in size than a mon star. D. It is cold. 6. Why can‘t you see light when you look at a black hole? A. For most black holes are so far away. B. As the star‘s gases burn, it stops giving off heat and light. C. As a star cools, its outer layers pull in toward its center. D. The gravity of a black hole is so strong that it sucks the light inward. C In life, we will succeed and fail often for reasons that are entirely out of our control. For instance, we can be incredibly nice and love someone deeply, and they may not love us back. We can work harder than anyone else in the office and still not be promoted to management. We can eat healthy food, exercise and stay away from alcohol and cigarettes, and still get sick. The bottom line is that life is not fair. That is a tough pill to swallow for many of us. As a result, some people shut down after being hit by even one unfair blow from life. They can‘t handle the fact that our efforts don‘t always get the results that we expect. But if we let life‘s unfairness defeat us, we will never receive the beautiful blessings (幸事 ) that life has in store for us. For example, my first marriage ended in divorce. To me, it felt very unfair. I had worked hard to be a good wife and mother. However, no matter what I did, I could not make the relationship work. I could have been shut down by that experience. I could have decided that if one person didn‘t appreciate me as a wife, then no one would. I could have given up. But I knew that I wanted to be married. I knew that I wanted to experience traditional family life. So I didn‘t let one seemingly unfair experience stop me from believing that I could one day be happily married. And then one day, I met this kind, thoughtful, generous man with whom I now have a wonderful friendship and marriage. But that wouldn‘t have happened if I had decided to give up after one failed marriage. What I‘ve learned over the years is that we can do all the things that deserve a good oute, but get bad things in return instead. When we are faced with life‘s seeming unfairness, our faith needs to jump in. When life doesn‘t go according to plan, we have to let go of the oute that we are looking forward to and keep trying, working hard and doing the right thing. Please don‘t be discouraged. Accept that life is neither fair nor straightforward. And by knowing that if we remain confident, we can drive our unfair experiences away and use them for our benefit. 7. We can learn from the first three paragraphs that ______. A. life doesn‘t often turn out the way we expect B. the author thinks life should reward us for our efforts C. unsatisfactory results simply mean your effort is not enough D. people should focus on the process rather than the outes 8. The author wrote about her unsuccessful marriage to ______. A. plain about the unfairness of her life and marriage B. tell readers how she met her second husband and became happily married C. express how proud she is for not being shut down by a blow from life D. show that we need to have faith and continue working for our goals 9. When we encounter unfairness in life, the author suggests we ______. a. do nothing but accept them b. be confident with ourselves c. keep doing what we should do d. find out what has gone wrong A. ab B. ad C. bc D. cd 10. The author wrote the article mainly to ______. A. share her experiences of unfairness in life B. tell us how to deal with life‘s seeming unfairness C. tell us that life has beautiful blessings in store for us D. explain why life seems neither fair nor straightforward D Americans are not famous for selfdeprivation(剝奪 ), but experts say we consistently fail to get a good night39。s sleep. The remended daily requirements should sound familiar: eight hours of sleep a night for adults and at least an hour more for adolescents. Yet 71 % of American adults and 85% of teens do not get the suggested amount. ―Sleep is sort of like food.‖ says Robert Stickgold, a cognitive (認(rèn)知的） neuroscientist at Harvard Medical School But, he adds， there39。s one important difference: ―You can be quite starved and still alive, and I think we appreciate how horrible that must be. But many of us live on the edge of sleep starvation and just accept it‖ Part of the problem is that we are so used to being sleep deprived and coping with that condition that we no longer notice how exhausted we really are. In 2021, sleep expert David Dinges at the University of Pennsylvania School of Medicine tested the effects of restricting sleep to eight, six, or four hours a night for two weeks. During the first few days, subjects sleeping less than eight hours admitted to being tired and lacking alertness. But by Day 4, most people had adapted to their new baseline sleepiness and reported feeling fine— even as their cognitive performance continued to decline Over time, they became so exhausted that they had difficulty concentrating on even the simplest tasks. ―The human brain works only capable of about sixteen hours of wakefulness a day， ‖ says Dinges. ―When you get beyond that, it can39。t function as efficiently accurately or well.‖ In the real worlds people overe their sleepiness by drinking coffee or taking a walk. But then they find themselves nodding off in meetings or worse, behind the wheel, Those short snatches of unconsciousness are what researchers call microsleep, a sure sign of sleep deprivation, ―If people