Using too much water or throwing rubbish into our rivers are clear ways that humans can put our water supply in danger , but we also affect our water supply in less obvious ways. You may wonder how paving(铺砌) a road can lead to less useable fresh water. A major part of the water we use every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave ，the less water can flow into the ground to become groundwater.

    Human activity is not responsible for all water shortages(短缺). Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall, but in any case, good management can help to make sure there is enough water to meet our basic needs.

    Thinking about the way we use water every day can make a big difference, too In the United States , a family of four can use 1.5 tons of water a day! This shows how much we depend on water to live, but there's a lot we can do to lower the number.

    You can take steps to save water in your home. To start with use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher (洗碗机)only when it is full 。Help your parents fix any leaks in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.

    Last year I ruined (毁) my summer vacation by bringing along a modem convenience that was too convenient for my own good: the iPad. Instead of looking at nature, I checked my email. Instead of paddling a small boat, I followed my Twitter feed (推特简讯). Instead of reading great novels, I stuck to reading four newspapers each morning. I was behaving as if I were still in the office. My body was on vacation but my head wasn't.

    So this year I made up my mind to try something different: withdrawal (退出) from the Internet. I knew it wouldn't be easy, since Fm bad at self-control. But I was determined. I started by giving the iPad to my wife.

    The cellphone signal (信号) at our house was worse than in the past, making my attempts at cheating an experience in frustration (沮丧). I was trapped, forced to go through with my plan. Largely cut off from email, Twitter and my favorite newspaper websites, I had few ways to connect to the world except for radio and how much radio can one listen to, really? I had to do what I had planned to all along: read books.

    This experience has had a happy ending. With determination and the strong support of my wife, I won in my vacation struggle against the Internet, realizing finally that it was I, not the iPad, that was the problem. I knew I had won when we passed a Starbucks and my wife asked if I wanted to stop to use the Wi-Fi. “I don't need it,” I said.

    However, as we return to post-vacation life, a harder test begins: Can I continue when Fm back at work? There are times when the need to know what's being said right now is great. And I have no intention (愿望) of giving up my convenience completely. But I hope to resist (抵抗) the temptation (诱惑) to check my email every five minutes, which leads to checking my Twitter feed and a website or two.

    I think a vacation is supposed to help you reset your brain to become more productive. Here I hope this one worked.

The Young Scientists Club was founded in 1999 with a clear and simple goal—to offer young children quality science-related products that will attract them with the wonders of scientific discoveries and increase their interest in science.

    All the products are designed by a team of Harvard graduates, scientists, educators and parents with one purpose in mind to combine fun and interest with quality and learning in each product. Of course, no product is put on the market before it has passed the final test.

    The Young Scientists Club was created to fill a void(空白) of good-quality science products for young children. They believe that children should know the exciting field of science at any early age with fun and bands-on games, activities and experiments.

    All the young scientists in the club are encouraged to continue their scientific adventures by exploring each different topic in more detail by entering online Young Scientists Clubhouse. There the young scientists can not only explore scientific topics and scientific experiments in depth, but can also e-mail Celsius with questions, results and comments. Celsius loves to e-mail all young scientists back.

Those who are at The Young Scientists Club have received many awards for their products. The Young Scientists Club is excited to realize its goal—-to take children around the world and take part in an educational scientific adventure that lasts a lifetime.

    “Don't tell anyone”. We hear these words when someone tells a secret to us. But it can be hard to keep a secret. We5re often tempted to “spill the beans"，even if we regret it later.

    According to Asim Shah, professor in the Menninger Department of Psychiatry and Behavioral Sciences at Baylor College of Medicine, US, keeping a secret may well "become a burden”. This is because people often have an “obsessive and anxious urge to share it with someone”.

    An earlier study, led by Anita E. Kelly, a scientist at the University of Notre Dame, US, suggested that keeping a secret could cause stress. People entrusted (受委托的)with secrets can suffer from depression, anxiety, and body aches, reported the Daily Mail.

    But with secrets so often getting out, why do people share them at all? Shah explained that people often feel that it will help them keep a person as a friend. Another reason people share secrets is guilt over keeping it from someone close to them. A sense of distrust can develop when people who are close do not share it with each other. "Keeping or sharing secrets often puts people in a position of either gaining or losing the trust of someone,” according to Shah.

    He added that talkative people could let secrets slip out (泄露). But this doesn't mean that it is a good idea only to share secrets with quiet people. A quiet person may be someone who keeps everything inside. To tell such a person a secret may cause them stress, and make them talk about the secret.

    Shah said that to judge whether to tell someone a secret, you'd better put yourself in their position. Think about how you would feel to be told that you mustn't give the information away. Shah also recommended that if you accidentally give up someone's secret you should come clean about it. Let the person know that their secret isn't so secret anymore.

    Researchers are often interested in how culture changes over time. All cultures go through periods of change and some cultures change faster than others. For example, in the past 10 years, Chinese culture has changed rapidly as western products have become popular. Other countries, such as France, have created rules to prevent their culture from changing too quickly.

    Even though cultures change at different paces, the causes of cultural change are quite similar around the world. One of these is technology and medicine. In the United States the invention and development of birth control pills and other measures helped parents to limit the size of their families. As a result, families grew smaller and parents could give more attention to fewer children.  On the other hand, new technology has also created emotional distance among families.

    Cultures also change when they come into contact with other cultures. Immigration, for example, often results in cultural change for both immigrants and the host culture. Immigrants often bring with them different ideas, food, music, language, and manners when they move to a new culture. In Canada, for example, the government has a policy of multiculturalism where immigrants are encouraged to share their background cultures with Canadians while adopting and accepting Canadian culture.

    Cultural change can occur due to larger events. For example, economic depression, war, and disaster can endanger societies, which must adapt to these challenges and events. Because of these changes in society, ideas and ways of life also affect the entire culture. For example, during World War II, many American men were sent far off to fight. Consequently, women were suddenly needed to work in the factories. As a result of this change, it is no longer culturally acceptable to believe that they should not have the right to work.

    Carrie Gracie is knowledgeable about China and its affairs. She also has a reputation as a generous colleague. She has resigned from her job as China editor because her employers will not pay her at the same rate as they pay the handful of men who do a similarly challenging and important job.

    She has resigned because she refused to go on colluding (共谋) with the BBC's dishonesty about its failure to give women and men equal pay for equal work.

    Gracie was recruited to the job, because she had all the talent and skills the BBC needed to cover the difficult international and domestic story of the rise of China. One of the conditions she set for taking it was equal pay with the BBC's other international editors, familiar names including Jon Sopel in Washington and Jeremy Bowen in the Middle East.

    Last summer, the government forced the BBC to publish which of the familiar names on radio and TV earned over ￡150, 000. The results exposed an astonishing pay gap. They also showed Gracie that her employers had misled her.

    Gracie sets out all her efforts to get her bosses to do what they had originally promised her, but they fail to respond adequately. Instead, they prevaricate (搪塞) and offer her a pay rise that still would not have delivered equality. They thought they could buy her off; they thought that the reputational hazard she was running would scare her away from the fight.

    The BBC is wrong this time! Gracie has chosen to resign rather than give in because she thinks that it is her responsibility to stop the BBC doing something stupid. She is fighting for women's legal rights.

    Gracie said she hoped she wouldn't be remembered as the woman who complained about money, but as a great journalist. She is proving that they are two sides of the same invaluable coin.

    Carrie Gracie's dispute with the BBC isn't about money—it's about dignity!