Deserts are found where there is little rainfall or where rain for a whole year falls in only a few weeks' time. Ten inches of rain may be enough for many plants to survive (存活) if the rain is spread throughout the year, If it falls within one or two months and the rest of the year is dry, those plants may die and a desert may form.

    Sand begins as tiny pieces of rock that get smaller and smaller as wind and weather wear them down. Sand dunes (沙丘) are formed as winds move the sand across the desert. Bit by bit, the dunes grow over the years, always moving with the winds and changing the shape. Most of them are only a few feet tall, but they can grow to be several hundred feet high.

    There is, however, much more to a desert than sand. In the deserts of the southwestern United States, cliffs (悬崖) and deep valleys were formed from thick mud that once lay beneath (在……之下) a sea more than millions of years ago. Over the centuries, the water dried up. Wind, sand, rain, heat and cold all wore away at the remaining rocks. The faces of the desert mountains are always changing--very, very slowly--as these forces of nature continue to work on the rock.

    Most deserts have a surprising variety of life. There are plants, animals and insects that have adapted (适应) to life in the desert. During the heat of the day a visitor may see very few signs of living things, but as the air begins to cool in the evening, the desert comes to life. As the sun begins to rise again in the sky, the desert once again becomes quiet and lonely.

    Imagine you are taking a walk on the beautiful beach. Just then, your feet step over something and you hear a crack (噼啪声) —an empty plastic bottle. Things like this are happening more often because of sea rubbish.

    Studies show that 80% of all the waste is from the land. The waste is mainly plastics (塑料制品) which are really hard to degrade (降解). So the rubbish will remain there for a long time. Some of the pollution is caused accidentally. For example, about 10,000 product-filled boxes are lost at sea every year from business ships. Sometimes people just throw things into the water from boats or land. Many large rubbish areas are formed in the North Pacific Ocean.

    Thankfully, the situation isn't ignored (忽视). Groups like the National Oceanic and Atmospheric Administration (NOAA) are taking action to help clean the sea. Since 2006,76 projects have cleared out 3,814 metric tons (公吨) of rubbish from the sea. Methods of rubbish cleaning include using machines to remove (移除) the waste away from the surface of sea water. Besides, special nets are set by the mouths of rivers to stop the rubbish before it reaches the sea. If everyone does his part, sea rubbish seems like a problem that can be solved.

What would you do if you see someone hurt badly? The following will help you to learn some important skills to give casualty (伤员) first aid.

{#blank#}1{#/blank#}

The first and most important thing you must do is to make sure the place is not dangerous. Can you see anything that might not be helpful to you? Can you hear anything that could be dangerous?

{#blank#}2{#/blank#}

When you see someone has been hurt, you may feel scared. If you feel yourself starting to be nervous, try to calm yourself down. For example, talk to people you trust about what happened, and you'll be relaxed.

{#blank#}3{#/blank#}

When someone needs first aid, talking to him will help him to stay calm and feel safe. Even if he does not answer you, you should still tell him what you are doing. It will let him know that you are helping him.

{#blank#}4{#/blank#}

Sometimes, the casualty will need more help than you are able to give. The best thing you can do is to phone some people for help. They can give you some useful advice or offer you some help.

{#blank#}5{#/blank#}

There are also many other things to do. Try your best to help the casualty. Asking people around you for help is really better than waiting for doctors. Besides, you can also try to keep in touch with his families and friends.

Has your mother or grandmother ever made embroidered (刺绣的)clothes for you? In the past, Chinese people often embroidered on hats, shoes and dresses. Some girls would even embroider on a sachet (香囊)as a gift for their lovers.

Shu embroidery comes from Sichuan. It is said that Shu embroidery is the old lest kind of embroidery in China. People began to make it during the Han Dynasty (206BC-220AD).They sold it to other countries such as ancient Rome.

Shu embroidery takes time. It might take as long as a whole day to finish just 10 cm. Embroidery workers need to divide each silk thread (丝线) into more than 10 or over 30 smaller threads. Each smaller thread is thinner than a human hair.

Meng Dezhi, who used to work at the Chengdu Shu Embroidery Factory，has been making Shu embroidery for over 40 years. She loves this form of art and wants more people to try it, so she gives lessons in universities. She said. "Although the work is hard, Shu embroidery stands for thousands of years of Sichuan culture. It is a symbol of Chinese culture as well."

Hi, everybody. Here we're in front of the South Gate. Go straight on, and you'll find the Panda House. Pandas are cute. They like to eat bamboo and lie down all day long. Every year, lots of visitors come here to see them. 

Walk along the road. To the north of the Panda House, you'll find the lions. Lions are the kings of the animal world. Remember that they're dangerous. Never go near them. 

Turn left, and to the west of the Lions' Area, you'll find the World of Birds. Birds make beautiful sounds when they sing. To the north of the World of Birds is the Monkeys' Forest. Monkeys are clever and funny. They jump around and make people laugh. 

Then turn right, and to the east of the Monkeys' Forest, you'll see the giraffes(长颈鹿). They're quite tall. Their long necks help them eat the leaves from trees. 

Northeast of the giraffes there's a bridge. Cross the bridge, and you'll see the elephants. Their large ears are like open fans. 

Here you can see all kinds of animals. Have a nice trip!