For thousands of years，people farmed the land. They grew fruits and vegetables. They hunted and fished for meat. They_______cloth, dyes(染料) and paper from plants. They used stone and metal for weapons and tools.

People progressed to making machines powered _______water and steam(蒸汽), and even later, by coal, oil, and petrol. Large cities were built. Factories _______of machines created jobs in the cities for thousands of people.   The Industrial Revolution(工业革命) changed the lives of many people because, for the first time, more people lived in cities than on _______.

Companies built power plants(工厂) to make_______to run the machines，factories and cities.

People did not realize these activities were_______the Earth. They didn't realize oil, gas, coal and minerals were being used up____.   _______cities grew bigger and spread across the land. plants and animals began to disappear. Their nature homes were destroyed(破坏) as people moved into new places.

As time passed, people began to _______ the need to protect the Earth and its natural resources(资源). They saw that plants and animals needed protection，so they wouldn't disappear forever. People joined together to tell________around the world to conserve(节约) our natural resources and care for the Earth. And so. Earth Day was born.   Each year，more and more people take part in Earth Day. What can you do to help?

Want to know what we can do to help make our city a better place to live? Why not take part in “Clean & Green Weekend”? Join us, and you can make new friends and help protect the environment at the same time.

The world is not hungry, but it is thirsty. It seems strange that nearly 3/4 of the Earth is covered with water while we say we are short of water. Why? Because about 97% of the water on the Earth is sea water which we can’t drink or use for watering plants directly. Man can only drink and use 3% of the water that comes from rivers and lakes. And we can’t even use all of that because some of it has been polluted.

Now more water is needed. The problem is: Can we avoid a serious water shortage later on? First, we should all learn how to save water. Second, we should find out the ways to reuse it. Scientists have always been making a study in this field. Today, in most large cities, water is used only once and then runs to the seas or rivers. However, it can be used again. Even if every large city reused its water, there still would not be enough water. What could people turn to next?

The sea seems to have the best answer. There is a lot of water in the sea. All that needs to be done is to get the salt out of the sea water. This is expensive, but it’s already in use in many parts of the world. Scientists are trying to find a cheaper way to do it. So you see, if we can find a way out, we’ll be in no danger of drying up.

Many Different Kinds of Trash

Garbage sorting is a big issue worldwide. In recent years, some Chinese cities have been working hard on it.

Shanghai has worked with Alipay to create a “green account(账户)” service for its residents(居民). Account holders get points by correctly sorting their garbage. Through the Alipay app, they can exchange the points for milk, phone cards and other products. The city is asking all of its residents to sort their garbage into four groups: wet, recyclable, harmful and dry.

※Wet waste is also known as household waste. “They are things you don’t want but pigs can eat,” Guangzhou Daily explained.

※Paper, metal, glass and other things that can be reused are recyclable waste.

※Harmful waste includes things like medicine, batteries and fluorescent bulbs(荧光灯泡).

※Any waste that is not wet, recyclable or harmful will go in the “dry waste dustbin”.

China is improving its waste sorting efforts. There is still a long way to go. But it’s never too late to learn how to sort your trash properly and protect the environment.

Also, different countries are using different methods to sort their trash.

※UK: A smart bin

A UK company has invented a “smart bin” to help with garbage sorting. People just need to drop their garbage into the bin. A camera and sensors(感应器) in the bin can tell what type of garbage it is and correctly sort it. The bin also compresses the waste so it takes up less space.

※South Korea: food aside

South Korea is using a method called “Pay For Your Trash” to encourage its people to reduce food waste. When throwing away trash, people have to separate their food waste from their other waste and put it in a dustbin. The smart dustbin then weighs the food. People have to pay for their food waste by scanning a bar code on the bin. The more they throw away, the more they will pay.

※Japan: careful sorting

Japan is leading the world in garbage sorting. They sort garbage so carefully that even plastic bottles and their caps go into different bins. Different types of paper products—newspapers, magazines and cartons—also have their own bins. There are also factories that make bags, clothes and dolls out of recycled waste.

How do you deal with plastic bags from the supermarket? Throw them away or recycle them? How about eating them?

The bags are not harmful to the environment. Humans and animals can safely eat them. An Indian company EnviGreen has made a bag with natural materials. It looks and feels just like plastic, but it can be broken down(分解) easily.

Ashwath Hedge who set up EnviGreen spent four years doing experiments with 12 natural materials. They included potatoes, corn, vegetable oil and bananas. He made the materials into liquid(液体) and used the liquid to make the bag.

Although the EnviGreen bag is more expensive than a common plastic bag, it has many advantages. According to The Wall Street Journal, it takes 1,000 years for common plastic bags to be broken down. But an EnviGreen bag can naturally be broken down in less than 180 days. It is also broken down in less than a day in water, and in less than a minute in boiling water. Hedge was happy to show it in his interview. He put an EnviGreen bag in water and ate it with a smile. 

There are more than 15,000 tons of plastic waste in India every day. But only 9,000 tons are processed(处理). In China, 3 billion plastic bags are used every day. Maybe the EnviGreen bag could be a solution to the world problem of plastic pollution.

Huge Waves Destroying Arctic Ice Faster than Expected

Ice covers much of the Arctic Ocean（北冰洋）. Some pieces of ice are huge, like moving islands. As temperatures have increased, however, some of the ice has begun to disappear. Scientists have discovered huge waves（海浪）in the arctic waters.

The waves were discovered by accident in May, 2010. Scientist Aleksey Marchenko and his students set out on a trip. They wanted to study the icy waters.

On May 2, the ship traveled east and stopped next to a large chunk of ice around 50 miles from the small island of Hopen. Marchenko prepared to lead his students out onto the Ice.

"We were ready to go but when I went out, I discovered many cracks（裂缝）around," he remembers.

He decided to move the ship deeper into the ice to keep safe. The farther in they went, he thought, the harder the ice would become. As they pushed forward, however, the ship experienced small waves, and then bigger ones. Soon, the waves broke up the ice around the ship into thousands of smaller pieces．

Within an hour, Marchenko and his team saw a wave that was about 13 feet high. The ship's navigation（航行）system finally recorded the largest waves. They were more than 20 feet in height. The waves were so strong that they forced huge pieces of ice to jump up and down, breaking the ice into smaller pieces within just one hour. Scientists had never imagined that the process could happen so fast. The waves in these areas used to be small.

The speed and force of the huge waves there makes it impossible to know in advance when they are coming. That could be dangerous for navigators and local communities who are unprepared for huge waves or depend on sea ice to protect them. Wildlife like polar bears and walruses that depend on sea ice to live is also in danger.

Some scientists think people will soon see even bigger waves in these icy waters. As waves break up ice, the seas will become more open, and the waves will get even stronger. There are stormy times ahead.

I’m glad to receive your email.                                                                                                                                         

If there is anything more that I can help with, please let me know. Yours,

Li Hua

42. 假如你是李华,你们学校倡议大家深入社区开展“垃圾分类,从我做起”的宣传活动。某英文报记者 Peter给你发邮件询问相关事情，请用英语给他回复一封邮件，告诉他活动举办的具体时间和地点，并分享你和你的同学们将要如何进行垃圾分类宣传。

提示词语: talk, importance, posters, trash bins, believe

提示问题: 1.When and where will you have the waste-sorting activity?

It’s important to sort out waste properly in our daily life.___________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Yours,

Li Hua