When I was a little kid, I dreamed of keeping on a dog. My parents disagreed, say that I was so young to take care of myself, let alone a dog. I didn’t give up. Instead, I tried to be independence and helped with housework. A few month later, my parents found that I had become considerate than before. They finally approve of my request. On my eight birthday, they bought me a lovely dog as the gift. Following my parents’ direction, I’ve learned how to raise the dog. I still miss those days that we accompanied each other.

March 11, 2011 was a holiday in Japan. Everything was going on like usual. Most people were at home while there came an extreme loud sound like thunder. Next, people's houses began to shake. Buildings cracked and water pipes bursting. In the town of Fukushima (福岛), the main street went up into the air, ten feet holes opened up in the ground, and buildings fell into ruins. People were shocking by the unexpected quake. Some ran up and down the street, while others were trapped in the buildings were looking out their windows for help. An earthquake that hit Japan was one of the strongest disaster in the world. Many towns were destroyed in the earthquake and a great number of people was killed. Most seriously, Fukushima nuclear accident happened.

Water is essential to life. However, 785 million people in the world (1 in 9) lack access to it. According to a report by the World Economic Forum (论坛), the water crisis    1    (be) the global risk in terms of impact on society.

We are working every day    2    (change) this situation. We’re here to bring safe water and sanitation (卫生设备) to all. By offering people this fundamental human need, we’re helping provide families    3    hope, health and the opportunity to break the cycle of poverty.

More than six times the population of the United States lives without a household water connection. These people,    4    (particular) women and children, must spend much time in getting water, instead of working, going to school or caring for    5    (they) families.

Access to safe water,    6    has the power to help people save time    7    ( waste) in fetching water when it’s close and not hours away, can protect and save lives. Access to safe water can turn problems into potential: unlocking education, economic prosperity (繁荣)     8    health.

Human    9    (being) deserve to define their own future, and water makes that possible. We've transformed more than 25 million lives with access to safe water and sanitation, and we can reach even    10    (many) people.

9 . Over their lifetimes, city trees will likely absorb less CO₂ from the air than forest trees. A new study finds that city trees grow faster and die younger than trees in forests. Studies have shown forests readily absorb CO₂. But there haven’t been much data on whether city trees grow, die and absorb CO₂ at the same rate that forest trees do. So Lucy Hutyra, an environmental scientist, and her colleagues at Boston University in Massachusetts decided to find it out.

To figure out how quickly trees were growing the researchers tracked their diameters (直径) of their trunks from 2005 to 2014. The team focused on red oaks and red maples growing on Boston streets. These grew four times faster than the same species did in a nearby forest. Faster -growing trees absorb more CO₂. Over the nine years the researchers have tracked these trees and found city trees absorbed four times as much carbon from the air as the forest trees did. The city trees also, however, were twice as likely to die.

City trees grow faster because they have less competition with their neighbors for light. In a forest, trees tend to grow close together, shading their neighbors. So few may get as much light as they want.

“Street trees also benefit from higher levels of nitrogen (氮气) in rainwater. Nitrogen is an element that helps plants grow. It’s also an ingredient (成分) of the. gas-burning cars’ exhausts. Some street trees also may have better access to water than trees in the country. That’s because the underground water pipes can leak,” says Hutyra.

Shaun Watmough, an environmental scientist, says it’s important to keep in mind that people plant city trees along city streets not just to absorb carbon. The trees also help clean the air, provide shade and make a city more beautiful even if it’s only for decades, not centuries.

10 . Sports can help you keep fit and get in touch with nature. However, whether you are on the mountains, in the waves, or on the grassland, you should be aware that your sport of choice might have great influence on the environment.

Some sports are resource-hungry. Golf, as you may know, eats up not only large areas of countryside, but also tons of water. Besides, all sorts of chemicals and huge amounts of energy are used to keep its courses （球场） in good condition. This causes major environmental effects. For example, in the dry regions of Portugal and Spain, golf is often held responsible for serious water shortage in some local areas.

There are many environment-friendly sports. Power walking is one of them that you could take up today. You don’t need any special equipment except a good pair of shoes; and you don’t have to worry about resources and your purse. Simple and free, power walking can also keep you fit. If you walk regularly, it will be good for your heart and bones. Experts say that 20 minutes of power walking daily can make you feel less anxious, sleep well and have better weight control.

Whatever sport you take up, you can make it greener by using environment-friendly equipment and buying products made from recycled materials. But the final goal should be “green gyms”. They are better replacements for traditional health clubs and modern sports centers. Members of green gyms play sports outdoors, in the countryside or other open spaces. There is no special requirement for you to start your membership. And best of all, it’s free.