Here I want to tell you some information about water.

    Water covers most of our planet. People can find it in oceans, lakes and rivers, and under the ground. Water moves in the environment by evaporation, condensation, and precipitation. The warm Sun helps water change into vapour and rise up into the sky. It is evaporation. The vapour in the air forms clouds in the sky. It is condensation. When the clouds get heavy enough, the water falls back to the ground as rain or snow. This is precipitation.

    Ocean water has too much salt in it. Much of the water travels far over the land. When it travels over the land, the water picks up salt from the rocks and soil. About 97.5% of the Earth's water is salty water. It is expensive to take salt out of the water.

    All people need clean water. They need it for drinking, for cooking, and for bathing. Some people in a village in South America did not have clean water. Their water was full of oil and dirty things. People there got sick when they drank the water. Other people heard about the problem. They sent empty water tanks (储水池) to the village. Rainwater fell into the tanks. Now the people in that village have the clean water.

    Electricity is an important part in our life. We can't see or touch it, but it is all around us. Our life will be terrible without electricity. But some people don't know that everyone should save electricity. When it is not completely dark, many street lamps (路灯) light up early in some streets. Some people don't turn off the lights when they leave the room. Some people are sleeping with the lights on. They are all wrong. Here I make some suggestions about stopping these things:

    *Turn on the street lamps on time. We light them from 7：00 p. m.～5：30 a. m. in summer, and from 5：30 p. m.~6：00 a. m. in winter.

    *If some small areas are very dark, just turn on a few lights.

    *The distance (距离) between street lights can be 50～60 meters. It can save electricity and money.

    *If there are some activities, such as fairs, we can make the lights bright；if there is no activity, lights needn't be too bright.

    Ask people to save electricity through TV shows, newspapers, and so on.

    Electricity is a valuable resource (资源). It helps us live well and conveniently. We should take action to save it at once!

    America is a mobile society. Friendship between Americans can be close and real, yet disappears soon if situations change. Neither side feels hurt by this. Both may exchange Christmas greetings for a year or two, perhaps a few letters for a while, then no more, If the same two people meet again by chance, even years later, they pick up the friendship.

    This can be quite difficult for us Chinese to understand, because friendship between us flows more slowly but then may become lifelong feelings, extending (延伸) sometimes deeply into both families.

    Americans are ready to receive us foreigners at their homes, share their holidays and their home life. They will enjoy welcoming us and be pleased if we accept their hospitality (好客) easily.

    Another difficult point for us Chinese to understand Americans is that although they include us warmly in their personal everyday lives, they don't show their politeness to us if it requires a great deal of time. This is usually the opposite of the practice in our country where we may be generous with our time. Sometimes, we, as hosts, will appear at airports even in the middle of the night to meet a friend. We may take days off to act as guides to our foreign friends. Americans, however, express their welcome at home. But they truly cannot manage the time to do a great deal with a visitor outside their daily routine. They will probably expect us to get ourselves from the airport to our own hotel by bus. And they expect that we will phone them from there. Once we arrive at their homes, the welcome will be full, warm and real. We will find ourselves to be treated hospitably.

    For Americans, it is often considered more friendly to invite a friend to their homes than to go to restaurants, except for purely business matters. So accept their hospitality at home!

Life in the future will be different from life today. Many changes will happen. But what will the changes be?

The population (人口) is growing fast. There will be more people in the world and most of them will live longer than people live now. 

Computers will be much smaller and more useful, and there will be at least one in every home. And computer studies will be one of the important subjects in school then. People will work fewer hours than they do now and they will have more free time for sports, watching TV and travelling. Travelling will be much cheaper and easier. 

There will be changes in our food, too. More land will be used for building new towns and houses for all the people. Then there will be less room for cows and sheep, so meat will be more expensive. Maybe no one will eat it every day. Instead (相反), they will eat more fruit and vegetables. Maybe people will be healthier. Work in the future will be different, too. Robots will do dangerous and hard work. Because of this, many people will not have enough (足够的) work to do. This will be a problem. 

What did people do to communicate in ancient times? Here are some very interesting answers to this question.

Alphorns（阿尔卑斯长号角） were once used to communicate in the mountains in Switzerland. They are very long and they are very heavy, too. So, alphorns are hard work to blow. Then why use them? Well, they make a loud sound which travels much further than the human voice. Herdsmen（牧民） used them to call cows in the distance for milking. At sunset, alphorns were also used to send a message down to villagers that all was well. These days, they're mostly used as musical instruments.

The people of La Gomera, an island in Europe, have their own special way of sending messages from mountain to mountain. They use a whistled（口哨） language called el silbo, which comes from their language Spanish. Whistling can be heard within five kilorneters, which means it can be used across much greater distances than shouting. El silbo can be used for all kinds of messages, including greetings and announcements. El silbo is used a lot less than it used to be, but primary school students in La Gomera have to leave it.

Did you know it 's also possible to send messages without making a noise? This is called visual communication, and it includes the use of flags and even smoke. Long ago, soldiers along the Great Wall of China used smoke as a warning. If they noticed the enemy from their signal（信号） tower, they lit a smoky fire. When soldiers in other towers saw the smoke signal, they lit fires, too. In this way, messages about the enemy's arrival could travel as far as 800 km in just a few hours.

It's Sunday afternoon and the weather is sunny and hot, My friends and I are in a large and beautiful park. We' re having a good time. 

Jack and Tom are swinging. Steve, Alice, John and Tim are playing hide-and-seek (捉迷藏). Rose, Mary and Lisa are skipping (跳绳). They re good at skipping. Susan is reading a book. Tina and Kate are chasing after my pet dog. They 're running around happily. 

We can see a lot of people in the park. Some are running and some are walking slowly. Look!

A boy and a girl are drawing pictures. Their parents are sitting next to them. They' re talking about something. 

Everyone is having a good time in the park. The park is a great place to have fun.