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    Research proves that nearly half of the cancers diagnosed(诊断) in the UK each year-over 130, 000 in total- are caused by life choices that include smoking, drinking and eating the wrong things.

    Tobacco(烟草) is the biggest factor, causing 23% for cases in men and 15.6% in women, says the Cancer Research UK report. Next comes a lack of fresh fruit and vegetables in men's diets, while for women it is being overweight. Lead author of the report, Professor Max Parkin, said: "Many people believe cancer is related to fate or in the genes(基因), and that it depends on luck whether they get it or not. Looking at all the evidence, it is clear that around 40% of all cancers are caused by things we mostly have the power to change."

    For men, the best advice appears to be: stop smoking, eat more fruit and vegetables and cut down on how much alcohol you drink. For women, again, the best advice is to stop smoking, but also watch your weight.

    In total, 14 lifestyle and environmental factors, such as where you live and the job you do, cause 134, 000 cancers in the UK each year.

    Some risk（风险） factors are well founded, such as smoking's link with lung cancer. But others are less well recognized. For stomach cancer, a fifth of the risk comes from having too much salt in the diet, data suggests. Some cancers, like mouth and throat cancer, are caused almost entirely by lifestyle choices. But others, like gall bladder cancer(胆囊癌), are largely unrelated to lifestyle.

    Public Health Minister, Anne Milton, said: "By making small changes you can cut your risk of serious health problems- giving up smoking, watching you drink, getting more exercise and keeping an eye on your weight."

    Watering plants is an important part of having a garden. But different plants have different needs. Plants like plenty of water, but how do you know what is too much or too little? Here are just a few helpful suggestions you may want to consider.

    3 Do's 3 Don'ts

    Water early.

    Water in the morning before it begins to get hot. It's a perfect time to water your plants. This way they are ready for the hottest parts of the day. Don't water too much.

    Although plants are usually thirsty, too much water can be harmful to their growth. If you notice the leaves are becoming yellow and falling off, it is a clear sign of too much water.

    Drain （排水） properly.

    Be sure to check the surrounding area of your plants regularly. The extra water should be drained well. Don't water late.

    This is especially important. Although not everyone will be able to do their watering in the early morning hours, try not to wait too late in the day. If you water in the afternoon when it is hot, lots of water will evaporate （蒸发）before reaching the roots. If you water in the evening, the roots will be too wet.

    Prevent insects.

    A thin, fine mist （喷雾） will prevent insects from setting on the leaves and flowers. Don't water the leaves.

    The most ideal place to begin is the root. This is where most of the growth and development takes place. In order for your plants to be strong, the roots have to be healthy.

    To really know what works well for your plants, watch them for signs of over watering or signs of not getting enough water. For more great advice on rose watering and growing roses, visit http:// www. my rose guide. com.

    Many animals hide to stay alive. They hide in many ways. Some animals hide in leaves; some animals hide in snow. Usually their colors or shapes help protect them. It's hard to see an Arctic bear in snow. Its white fur helps protect it. Chameleons(变色龙) can hide by changing colors. Their skin turns the same color as what is around them. Some chameleons can change colors in five minutes.

    Many animals try to look bigger than they are to stay alive. Some animals can make other animals think they are very big. If they look very big, animals that are looking for food will run away. Bears can walk on two legs. They look very, very scary. Some animals will run away from them.

    Many animals try to stay around other animals. This helps them stay alive. Zebras stay close together so that they can help each other look out of danger. Seeing many stripes at once can also confuse animals that want to eat them. Some birds stay in a circle, each toward a different direction. In this way they can also help each other stay alive by looking around for animals that many want to eat one of them.

    What is the most stressful (有压力的) thing in school? It is probably exams. Exams can put us under a lot of stress. But some students do better under stress, while others do not. So, why do some students behave better under stress?

    It all comes down to dopamine (多巴胺). Dopamine is a chemical in our body that sends signals in the brain. It has many important roles: influencing memory, attention and how we learn.

    Our brains work best when there is a balance (平衡) of dopamine—not too much or too little. Our brains control dopamine in two ways. It either takes out dopamine quickly, or bit by bit. Exam success can be connected to how fast dopamine goes back to a balance, according to new research from the University of Missouri, reported Yahoo.

    What happens when we take an exam? If you become stressed, your brain will start to overload on dopamine. It is like a cup overflowing with water. The quicker you are able to go back to a balance of dopamine, the quicker you can focus, helping you do better on a test.

    Scientists found that, during a test, people who slowly got back to a balance of dopamine scored 8 percent lower. That's the difference between a good mark and a bad mark.

    But don't fear, there is good news for every student. The study also found that the more practice you get, the less stressed you will be. So, it turns out that     .

    The world got a glimpse(一瞥) of one of the greatest mysteries of our universe(宇宙) on April 10.

    That′s when the first image of a black hole was shown to the public. The picture was created by a network of eight radio telescopes(射电望远镜).

    "We have seen what we thought was unseeable, "says Shep Doeleman. He led the effort to create the image.

    The black hole is at the center of galaxy (星系)named Messier 87, some 55 million light﹣years from the earth, and is 6.5 billion times the mass of the sun.

    The image shows the gas, dust, and stars that move around the black hole before disappearing into it. It does not truly show the black hole, because not even light can escape its gravity. Black holes, like vacuums, suck(吸)in everything that gets too close.