People usually check whether their keys, purses and phones are with them before going out, but many people in China now have one more important thing to take--a mask(口罩). They hope it can protect them 1 terrible air.

    Many cities in China saw a lot of foggy days in April. In Beijing, there were eight days in April full of smog. It is dirty air 2 looks like a mixture of fog and smoke. The smoke is mainly from cars and factories in cities. Poor air is bad for people's health, 3 for children and old people. They fell ill easily and the 4 were full of people. They had problems with their noses and lungs.

    So it's necessary 5 people from doing so many bad things to the environment. For example, people should use cars less and   6 burn lots of coal and gas. Government needs to take measures to make factories stop pouring 7 waste air into the sky.

    Three students from No. 4 High School in Beijing 8 a report to advise how to protect the environment. They suggested  9people should plant more trees and act off fewer fireworks for celebration. We hope more people will join us in 10 a difference. In this way, the blue sky will certainly return for good.

      Our factories and homes burn coal and oil. Every year we have forest fires somewhere. Many scientists believe that the weather is changing.

      The earth will perhaps be warmed by about 7℃ at the South Pole(极) and the North Pole. The ice will be melt(融化). The sea level(平面) will rise by about 7 meters. As a result, water will cover cities like London, Tokyo and New York. Some ports(港口) and towns along the coasts will disappear under water.

      Some other scientists think that the dust, smoke and pollution from coal, wood and oil fires will block out(封闭) the ultraviolet rays(紫外线). Then the earth will become colder and great sheets of ice will cover Europe and North America.

      When chemicals in the air mix with rain, we have acid(酸) rain. Acid rain can bring us great harm. It destroys(破坏) forests and kills life in lakes and rivers.

      People are beginning to see how serious the problem is. They find it important to work with nature instead of against it. They are trying to save the earth in many different ways. But one of the most important things to do is to make people understand that saving the earth is saving ourselves.

    Compared with other European countries, lifestyle in Italy is slower and more relaxing in its own way. Italians love to chat over a cup of coffee, go out for a walk in the middle of the day, and enjoy long lunches and dinners.

    The family is important to Italians. They can't think of spending a day without talking about their parents and children, or a weekend without a family lunch or dinner. Italians living outside their country miss their family a lot.

    Italians like simple life. Their days start and end with a cup of coffee. A cup of coffee after every meal is a must. Italians love to spend time over a hot cup of coffee and even hotter conversation with friends. Topics are usually about family, football and politics(政治).

    Sport is a very important part in lives of many Italians. Football is their favorite sport. There are hundreds of football clubs with top football teams in Italy. Also, many top players from all over the world play in Italy. Volleyball is also popular and so is rugby, with the top rugby team playing for the European Challenge Cup.

Every Italian province, city, town and street has a historical event that took place there and the Italian calendar is filled with national holidays that they love to celebrate.

    People have understood that kindness is good for the person who receives help. For example, when we give food to a hungry person, he is lucky. However, scientists have recently begun to study the effect(影响)of the kindness on the person giving it. What they have found is that doing good is good for the doer(行为者).Acts of kindness can improve health, help a person reach goals and even add years to a person's life.

    The first study to show the connection between doing good and living a long life was a study on aging(衰老). Beginning in 1956, scientists studied a group of married mothers for 30 years. They thought the women with the most children would die first. But the number of children a woman had did not matter. Wealth did not matter. Education did not matter. What did matter was whether they volunteered. Women that volunteered had fewer diseases during their life.

    Many other studies have found the same positive(积极的)effects. Helping other people improves long-term health. The gains are the same for men, women, old people and the young. Those who volunteered had fewer serious diseases than those who did not volunteer. This included diseases such as heart attack, cancer and stroke.

    Scientists are studying many possible causes. One possible cause is an increase in antibodies(抗体)，which help fight against disease. One study showed the body produces more antibodies after an act of kindness.

    Another one is an increase in Oxytocin(催生素)，it is a chemical that fights the effects of stress from life. Scientists have found a link between being kind to people and an increase in the chemical oxytocin.

    You can not see any object unless light from that object gets into your eyes. Some of the things you see give off light of their own. The sun, the stars, a lighted lamp are examples that can be seen by their own light. Such things are luminous. Most of the things you see are not giving off light of their own. They are simply reflecting light that falls on them from the sun or some other luminous bodies moon. For example, does not give off any light of its own. It is non-luminous. You see it because sunlight falls on it and some of it reflects in our direction. So moon light is only second hand sunlight.

    When you look at a book, it sends to your eyes some of the light which falls on it, and you see the book. If light could be kept out from where you are so that there would be no light for the book to reflect, then you could not see the book even with your eyes wide open.

    Light travels so fast that the time in which it travels from the book you are reading to your eyes is so short as if there were no time at all. Light reaches us from the moon, which is about 380 000 kilometers away, in only a little more than a second.

    Do you often run outdoors to keep healthy? Have you ever thought about how running helps to clean up the earth? Sometimes a creative mind can bring us a win-win(双赢)situation.

    Plogging, a new way to exercise, began in Sweden(瑞典).The name "plogging" comes from two words the Swedish(瑞典的)word "plocka", which means" to pick up(捡起)", and the word" jogging", which means "to run slowly". A Swedish man called Erik started the movement. He saw rubbish here and there when riding to work each day. He became worried about the dirty environment and decided not to go to work by bike any more. Instead, he began to run to work and pick up the rubbish at the same time. To his joy, more and more people followed him and soon plogging became popular.

    Many people choose plogging instead of just jogging because they think plogging is a good way to help clean up the earth. Sometimes rubbish is difficult to collect because it may scatter all around. But if the runners pick up the rubbish on the way, it is quite different. After all, many hands make light work. Another reason is that plogging burns more calories(卡路里).According to a research, plogging for 10 minutes burns 48 calories, while usual jogging for 10 minutes burns about 39 calories.

    Everyone on the earth should play a part in cleaning it up! It's time for us to take action together. So ready? Let's plog tomorrow!