Nuclear radiation has a certain mystery, partly because it cannot be detected  by human senses. It can't be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around but we can't detect them or sense them without a radio receiver. Similarly, we can't sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things. At very high levels, radiation can kill an animal or human being outright by killing masses of cells in important organs. Even the lowest levels can do serious damage. There is no level of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be serious. This is the case when only a few cells are hit, and when they are killed outright. Your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They reproduce themselves in an unusual way. They can grow into cancer. Sometimes this does not show up for many years. This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the knowledge of the person at the time that damage has occurred. A person can be irradiated and feel fine, then die of cancer five, ten, or twenty years later as a result. A child can be born weak or easy to get serious illness as a result of radiation absorbed by its grandparents. Radiation can hurt us so much that it can   _  . A) kill large numbers of cells in main organs B) replace cells which may grow into cancer years later C) affect the healthy growth of our younger generation D) A and C
D


My mother-in-law, Dorothy, is showing me the red notebook that's almost as precious to her as my husband's baby pictures. Inside the notebook is a list of the books she has read since 2007. For some people waking up in the middle of the night is a terrible thing. But for my mother-in-law, that time is a gift. At 87, she is getting the education she never had by working her way through great literature. She has now read close to 100 books, including every single novel by Anthony Trollope, Charles Dickens, Jane Austen, Edith Wharton, Henry James and Thomas Mann. My mother-in-law discusses her passion with the enthusiasm of a young girl, although she can also be a very tough critic, writing "VG' for " very good" in the margins next to her favorites. So far, only a handful of books have received the top prize. Born in Ridgefield, Conn, Dorothy was the youngest daughter of an Italian gardener. She taught herself English by reading The New York Times. Eager to come to Manhattan, she became a nurse, married a dentist and spent the next several decades keeping the house and raising a family. In her later years, she put her nursing skills to good use by taking care of my father-in-law, who had lung cancer. There were many trips to the emergency room in the middle of the night and then a long hospital stay. She stayed awake to watch over him for 15 hours a day. Always a light sleeper, she developed sleeplessness as a result of the stress. It worsened after he died. Deeply sad and lonely for the first time in her life, she began waking up around 2am. Julian and Sylvia, the elderly couple next door suggest she read literature. And so Julian, a great lover of literature, became her "professor", providing books from his large library. Suddenly turned onto a world of amazing characters. What helped Dorothy get over the sadness and loneliness of losing her husband? A) Living with her son. B) Reading literature. C) Seeing her son's baby pictures. D) Talking with neighbors.
B


Q: Money is the root of all evil and new study claims there may be some truth behind the saying.Scientists at the University of California, Berkeley, US,announced on February 27 that rich people are more likely to do unethical   things, such as lie or cheat, than poorer people. The scientists did a series of eight experiments. They published their findings online in the Proceedings of the National Academy of Sciences (PNAS,<<>> ). They carried out the first two experiments from the sidewalk near Berkeley. They noted that drivers of newer and more expensive cars were more likely to cut in on other cars and pedestrians at crosswalks. Nearly 45 percent of people driving expensive cars ignored a pedestrian compared with only 30 percent of people driving more modest cars. In another experiment, a group of college students was asked if they would do unethical things in various everyday situations. Examples included taking printer paper from work and not telling a salesperson when he or she gave back more change. Students from higher-class families were more likely to act dishonestly. According to the scientists, rich people often think money can get them out of trouble. This makes them less afraid to take risks. It also means they care less about other people's feelings. Finally,it simply makes them greedier."Higher wealth status seems to make you want even more,and that increased want leads you to bend the rules or break the rules to serve your self-interest," said Paul Piff, leading scientist of the study. Piff pointed out that the findings don't mean that all rich people are untrustworthy or that all poor people are honest. He said the experiments were to show how people living in different social situations express their instincts and values in different ways. What does the article really want to show us? A) Money is the root of all evil. B) The rich are more likely to act badly. C) The saying is unreasonable. D) All rich people are untrustworthy.
A: B


Q: I was at a dance club when I was nineteen. One day my new friend walked with me to my car. It was a very cold night. As we were walking to my car, a man walked up to us. Behind him was a woman pushing  _ with a child inside who was about 2 years old. The child had only a jacket on and it wasn'tzipped . The man began to tell us he wanted to borrow some money for the night and that he had a job but no place to live and was waiting for his first paycheck. He confirmed he could get our mailing address and mail the money back to us. The guy I was with reached into his pocket to give this man a $20 bill. As the man was extending his hand out to take the money, I put my hand on my new friend's hand and said, "Can I talk to you for a minute?" I told him some people earned money by begging and that they always cheated those with soft hearts. And if they were truly worried about their child being out in the cold, they would have at least zipped his jacket. My friend looked at me with disapproval and said, "Michael, I know there are some people out there that take advantage of others. I also know some people out there that are one paycheck away from being homeless. If I gave $20 to 10 people and only one of them really needed it and used it for the right thing, it was worth it." I am now thirty-seven years old and have never forgotten what he said to me. I don't even remember his name now. But I do remember that this experience changed my perspective . We can infer the author could learn from the experience that  _  . A) one should be very kind to everyone B) anybody has a time when he needs help C) one should do whatever is worthy actively D) one should keep away from those poor

A: C