There is little rain in desert. Because deserts are so dry, they have no "quilt" to help stop the soil from going away. As a result, they may get very hot during the day with the sun shining, but don't hold the heat overnight. Many deserts can quickly get cold once the sun goes down. Some deserts can reach temperatures of over 100 degrees F during the day and then drop below freezing (32 degrees F) during the night.

The largest hot and dry desert in the world is the Sahara Desert in Northern Africa. The Sahara is a sandy desert with great sand hills. It covers over 3 million square miles of Africa. Other large deserts include the Arabian Desert in the Middle East, the Gobi Desert in Northern China and Mongolia, and Kalahari Desert in Africa.

Animals that live in the desert are also used to needing little water. Many get all the water they need from the food they eat. Other animals keep water that they can use later. The camel stores up fat in its hump while other animals keep something they need in their tails.

Only certain types of plants can live in the terrible environment of the desert. You won't see a lot of tall trees in the desert. Most plants have a way to keep water in their leaves, or trunks so they can live a long time without water.

Now deserts cover around 20% of the world's land, but they are growing. This is called desertification and is caused by different reasons including human activities. The Sahara Desert is growing larger and larger each year. What should we do with it ?

   The population of the Earth is growing faster. It is important that we look after the Earth. We need it! The Earth gives us a lot of things. We also give the Earth a lot, but some of the things are not good.

   In nature, when something dies, other animals and plants get food from it. Every animal or plant gives food for other animals or plants. However, animals can't get food from many of the things that we "give" the Earth. Animals and plants can't eat metal, plastic and glass. These things will stay in the ground for many, many years.

   Some rubbish is very dangerous for plants and animals. In some places, many animals live together. One animal makes food for many more animals. If we put rubbish and chemicals in the water, the plankton(浮游生物) can die. If there isn't any plankton, many animals have nothing to eat.
   So what can we do? Don't leave any rubbish in the countryside! Don't make so much rubbish!

    Hi, everyone. I'm Tina. I think our life in 2060 will be different from our life at the moment. There will be many robots in my house. Because robots will be cheap. And these robots will help my family do many kinds of work every day. Every morning the clock-robot will ask me to get up. Then the clothing-robot will dress me quickly. Next the kitchen-robot will make breakfast for me. When I get out of the house with my schoolbag, a car-robot will wait for me. After I show it my school ID card, the car will go. And then the car-robot will check my homework. When we get to school, the car-robot will say to me "See you tomorrow, Tina. Good luck."

    In the morning, I will have three lessons with my classmates. We'll study on the Internet. We'll use the e-book. The teachers are all robots. They are in different sizes and they can answer any question about any subject. In the afternoon, we'll go to the science lab to have two classes in a new plane. After class, we'll play football with robots. My classmates and robots can all be my friends. Don't you think the life with robots in the future will be fantastic?

Sea turtles(海龟) live in the sea most of the time. The beaches in Florida are home to sea turtles. Female sea turtles come here from the ocean to lay eggs. Then they return to the ocean. However, the number of some of these turtle species(种类) is falling. They are in danger, so people in Florida work together as a community to protect them.

Some volunteers take direct action to help the turtles. They look closely at the sand to find out where the sea turtles lay their eyes. Then they help bury(埋藏) the eggs in order to save them from being destroyed. They are helpful in people who are studying sea turtles.

Florida's government has passed laws to save the turtles. One of these laws is "Florida's Marine Turtle Protection Act". This law prevents anyone from destroying sea turtles' nests or eggs. It helps protect the turtles from dying out.

People also work together to save the turtles through organizations(组织) like the Sea Turtle Conservancy. For example, the bright light from buildings near the beach can influence sea turtles. It may make the baby turtles get lost, leading to many of them do not make it to the ocean and even die. The Sea Turtle Conservancy works with house owners to make the lighting in their buildings sea turtle friendly. They also advise people to turn off their lights at night if they live close to the beach.

In a word, everyone can do his or her part to protect sea turtles and their living places. People in Florida can work as volunteers to clean up the beaches and pick up their own litter. Everyone in the community has the ability to make a difference!

Hi, I'm a student in Beijing. I'm 1 here, so I don't have many friends now. Can you be my 2 ?

Now let me introduce（介绍）myself. I'm Bella. I'm thirteen. I'm good at English, so I can3 you with it.

My favourite colour is 4 , so I have many blue things. Look, 5 bag is blue. My favourite 6 of the week is Friday, because we have a music class that day. I love music. I listen to music after school. I also like to7 songs in my free time. My friend Lena thinks I'm a good writer.

My favourite sport is 8 . I can play it well. Do you like playing it, 9 ? Tomorrow is 10 and I don't go to school. We can meet and play table tennis. My 11 is 564 736. You can call me. And I also like swimming on 12 days, because it can make me cool. We can also go swimming together 13 summer.

That's all about me. If you want to 14 more about me, you're welcome to call or write to me!15 for listening to（听）me.