Technological change is everywhere and affects every aspect of life, mostly for the better. However, social changes are brought about by new technology are often mistaken for a change in attitudes.

    Our body clock, or natural body rhythm, influences our energy and alertness. Paying attention to it can help us choose the suitable time of the day when we best perform specific tasks.

    The reality, however, is that most of us organize the time around work demands, school deadlines, commuting or social events. Doing whatever the body feels like doing is a luxury in today's fast-paced modern society.

    But that doesn't mean it isn't worth trying. Obeying our body clock has significant health benefits. Disrupting our natural body rhythm, on the other hand, has been linked to problems such as depression, obesity, or headache, says Steve Key, a biology professor.

    When the body clock can synchronize (使…同步) the rhythms of its natural processes, it “gives us an advantage in daily life”, says Key.

    According to him, when it comes to cognitive (认知的) work, most adults perform best in the late morning. As our body temperature starts to rise just before awakening in the morning and continues to increase until midday, our memory, alertness and concentration gradually improve.

    However, he adds, our ability to concentrate typically starts to decrease soon thereafter. Most of us are more easily distracted (分心) between noon and 4 pm.

    Alertness also tends to fall after eating a meal and sleepiness tends to peak around 2 pm, making that a good time for a nap.

    Surprisingly, tiredness may increase our creative powers. For most adults, problems that require open-ended thinking are often best dealt with in the evening when they are tired, according to a study in the journal Thinking & Reasoning.

    When choosing a time of the day to exercise, paying attention to your body clock can improve results. Physical performance is usually best from about 3 to 6 pm, says Michael Smolensky, a professor of biomedical engineering.

    Of course, not everyone's body clock is the same, making it even harder to synchronize natural rhythms with daily plans.

    Many facts suggest that children are overweight (超重的) and the situation is getting worse, according to the doctors. I feel there are a number of reasons for this.

    Some people blame the fact that we are surrounded by shops selling unhealthy, fatty foods, such as fried chicken and ice cream, at low prices. This has turned out a whole generation of grown-ups who seldom cook a meal for themselves. If there were fewer of these restaurants, then probably children would buy less take-away food.

    There is another argument that blames parents for allowing their children to become overweight. I agree with this, because good eating habits begin early in life, long before children start to visit fast food shops. If children are given fried chicken and chocolate rather than healthy food, or are always allowed to choose what they eat, they will go for sweet and salty foods every time, and this will carry on throughout their lives.

    There is a third reason for this situation. Children these days take very little exercise. They do not walk to school. When they get home, they sit in front of the television or their computers and play computer games. Not only is this an unhealthy pastime (消遣), it also gives them time to eat more unhealthy food. What they need is to go outside and play active games or sports.

    The above are the main reasons for this problem, and therefore we have to encourage young people to be more active, as well as steering them away from fast food shops and bad eating habits.

    Rosa Parks became famous in 1955 when she refused to give up her seat on a bus to a white passenger in Montgomery, Alabama. She was important in the movement for civil rights（民权） in the American South during the 1950s and 60s. At the time, blacks in the South were forced to sit in the back of public buses and to give up their seats to white people.

    Parks moved to Detroit, Michigan, in 1957 to escape death threats. She continued living in Detroit until her death in 2005, at age 92. But the house in Detroit where Parks lived for many years was abandoned and scheduled to be torn down. Her niece, Rhea McCauley, bought it for $500 to stop it from being destroyed. She then gave it to American artist, Ryan Mendoza.

    Mendoza and others took it apart and then sent it across the Atlantic Ocean to the German capital of Berlin. There, he led efforts to rebuild the house. It now is behind his own house in Berlin. It gets daily visitors, although it is difficult to find, Mendoza said.

    But less than a year after the house was rebuilt in Berlin, Mendoza decided it should be returned to the United States. He made the decision after deadly violence took place at a recent white nationalist event in Charlottesville, Virginia. That incident increased calls for removing statues of Confederate（美国南部联邦的） leaders from the Civil War in the U.S.

    Mendoza said there are not enough civil rights monuments "to balance things out" with the Confederate statues. He said the Rosa Parks house belongs back in America "Imagine if the house were on a public setting in a prominent city in the U.S.," Mendoza said. "That's an education tool that shouldn't be denied by the American people. They have to know their past."

    The house would be welcomed back in Detroit. Detroit has failed to protect historical homes in the past. Such houses include the former home of Ralph Bunche, the first African-American to win the Nobel Peace Prize. Detroit's failure to protect history also is shown by the loss of the Rosa Parks house, Hammer said.

    Buying new clothes isn't an easy matter for everyone, here are some tips(建议) for you .When you want to go shopping, decide how much money you can spend on new clothes. Think about the kind of clothes you really need. Then look for those clothes you really need. Then look for those clothes on sale.

    There are labels(标签) inside all new clothes. The labels tell you how to take care of your clothes. The label for a shirt may tell you to wash it in warm water. A sweater label may tell you to wash in cold water. The label on a coat may say "dry clean only", for washing may ruin this coat. If you do as the directions(说明)on the label, you can keep your clothes looking their best for a long time.

    Many clothes today must be dry cleaned. Dry cleaning is expensive. When buying new clothes, check to see if they will need to be dry cleaned. You will save money if you buy clothes that can be washed.

    You can save money if you buy clothes that are well-made. Well-made clothes last longer. They look good even after they have been washed many times. Clothes that cost more money are not necessarily better made. They do not always fit better. Sometimes less expensive clothes look and fit better than more expensive clothes.

    PARIS—A scaffolding(脚手架) firm that has worked on the roof of Notre Dame said some of its workers had smoked on the site, but ruled out that a cigarette butt(烟蒂) might have started the fire that destroyed the cathedral's oak－framed roof last week.

    A spokesman for family－owned Le Bras Freres, confirming a report in French weekly Le CanardEnchaine, told Reuters that some workers of its Europe Echafaudage scaffolding unit had informed police that they had "sometimes" smoked on the scaffolding, despite a smoking ban on the site.

    "We blame it. But the fire started inside the building...so for company Le Bras Frères this is not a hypothesis(假设), it was not a cigarette butt that set Notre Dame de Paris on fire, " Le Bras Frères spokesman Marc Eskenazi said. TheCanardEnchaine reported that police had found the remains of seven cigarette butts in the burnt－out cathedral."This is not wrong, " said a source close to the investigation, who declined all other comment. Eskenazi said it was impossible to set a log on fire with a cigarette butt and questioned how cigarette butts could have been found on the site."If cigarette butts have survived the fire, I do not know what material they were made of." he said.

    Europe Echaffaudage also ruled out the possibility that the fire might have been started by an electricity incident at one of the two lifts on the site."The lifts' electricity was perfectly within specifications and well maintained, " he said. He added that the two lifts were on the outside of the building, situated at 45 and 65 metres from the base of the spire(尖顶), where the first smoke and flames had been spotted and that the workers had cut the power to the lifts at 17:50 when they had left the site for the day.

    TheCanardEnchaine also reported that electrical wiring ran through the roof of the cathedral, but the church administration denied that safety norms had not been respected."Nothing was ever done without the approval of the state...There were no wires dangling, everything was properly installed," Notre Dame spokesman Andre Finot said.In 2012, electrical engines had been installed to sound the bells in the spire.