In 2045, I will live in a smart house. It won't be very1, because the earth will be more crowded in thirty years, and there won't be much room for me to2my house. But it will be comfortable and full3smart furniture (家具). In the morning, my bed will “stand up” and wake me up.4I don't need an alarm clock. After I take a shower and then go into the5, my breakfast is already ready.6cooks it? My smart table does.

    I will spend the daytime in my office. But I can still know what is 7in my house. Is there8visiting me? Does my dog do well alone at home? I can watch all of these on my phone.

    When I arrive home in the evening, the lights will “know” I'm back and they will9themselves. I10I will have such a cool house. Do you think so?

    It's very important that we all recycle.In nature,everything1 again.For example,when an animal dies,it becomes2 animal's food.Nothing is wasted.But humans have created things like plastic bags which can't be3 down by nature.Our4 kills animals and pollutes water and soil.5 we continue making too much rubbish,the problem will only get worse.If nature can't reuse the rubbish,we must recycle6 .We should clean up the rubbish we've made because nature can't.

    Recycling is also the right thing to do for another reason.The earth is rich in natural materials like water and trees,7 these materials are not endless (无尽的).We use up our natural materials8 faster than the earth is able to reproduce (再生) them.For example,each year we cut9 more than 6,000 square miles of forest.But it takes an average of 25 years for a new tree10 .

    Recycling can help us save the earth,so let's take action right now.

    The undersea world is very beautiful. Now more and more people want to 1 in the water to find the secret there. Scuba diving (水肺潜水) is a new sport today. It can take you into a wonderful undersea world.

    If you are lucky, you will 2 find many strange animals in the sea. Some are as 3 as a school bus. Some are so tiny that you may not  4 them at all.

    During the day, there is enough 5. Everything is blue and green. When fish swim nearby, you can catch them with your hands. When you have bottles of air on your back, you can stay in 6 water for a long time. However, you can't dive too deep. And you must be very 7 when you are in deep water, because something dangerous may happen unexpectedly.

    The deep sea is not an easy place to live in. It's cold, and it's 8 too. The deeper it is, the less sunlight there is. At about 3,000 feet, there is no light at all.

    Besides the cold and darkness, deep-sea animals face a third 9 —other animals. Animals eat! Many animals eat plants. However, some animals eat 10. This means these sea animals have two big jobs. They need to find animals as food, and they have to try not to become other animals' meal.

    The world of the out-of-doors is full of secrets (秘密). And they are    1interesting that quite a lot of people are busy 2them.

    All around us are birds, animals, trees and flowers. The facts about how they3 and grow are as interesting as anything could be.

    Do you know that one of the great presidents of the USA 4 hours and hours5birds? A businessman who lived near New York became so 6in insects(昆虫) that he began to get 7 together. He now has more than one thousand different kinds of insects carefully 8in glass boxes.

    Come up with me, and I will help you find some nature's secrets. Let us go9 through the woods and fields. Here we shall find how a rabbit tells the others there is danger. We shall 10 a mother bear and her young ones as they look for11and get ready for winter sleep. We shall watch bees(蜜蜂)dancing in the air to let other bees know 12 they can find food.

    I will 13 you many other interesting things, but the best thing that I can14 you is to keep eyes and ears15 when you go out of doors. Nature tells her secrets only to people who look and listen carefully.

    Many people like to see animals in the zoo. But do you know most of the animals in the zoo are very 1? Animals usually live in the forests or mountains. They like to live 2. But the life in the zoo is quite 3 from that in the forests and mountains. They have to stay in cages all day and wait for the zoo 4 to feed them. They can't come out of the cages. So they have to walk round and round.

    The wildlife park can solve all these 5 for them. All the animals live in the open air everywhere in the 6. They 7 stay in cages. They can run, jump and play with other animals happily. The most important thing is that they are free and happy, and they are protected there. People are not allowed to hunt in the wildlife park.

    Some of the animals in wildlife parks are friendly, but some are fearful, such as lions, wolves and tigers. But it's not dangerous 8 the animals in wildlife parks. You can take a bus to see the animals. It will be very 9 if a tiger or a bear looks at you through the window. But don't worry. 10 will happen. You are quite safe inside the bus.