If you ears are working well, you hear sounds all the time. You can't switch（关掉）your ears off, even when you are asleep.

Listening

    When you really want to listen to something, you tell brain to focus on that sound. If your ears are healthy and are both working well, they can turn down other sounds while you focus on what you want to hear. If one ear isn't working __________ the other, they can't do this as well. If you hearing cells（细胞）have been damaged by too much loud noise or music, what you want to hear can get mixed up and lost in the other sounds around. With healthy ears you can choose what you want to listen to, but you can't choose what you hear.

Understanding

    Your brain deals with the received sounds and tells you what they mean. Some people have problems understanding what they are hearing because their ears don't work well and they don't hear all the sounds. They brain does not get enough information to understand the messages or they may be mixed up.

Selective（选择的）hearing

    Lots of mums and dads think that kids have this “problem”. They think that you select what you are going to hear and what you can't hear! Many mums say that dads do this, too. In fact, this is something we may all do to try and make our lives a bit easier. Some children wrote what they liked to hear and what they didn't like to hear.

    We always think classical (古典的) music fans are quiet and shy, and lovers of rap (说唱音乐) are outgoing.{#blank#}1{#/blank#}According to a study in Edinburgh, it is.

    Professor North, who did the study, says that people often show their personalities through the kind of music they listen to. More than 36,000 people from around the world joined-the study.{#blank#}2{#/blank#}Here are some of the results:

Western and country music fans are hard-working and not shy.

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Classical music fans are quiet.

Rap fans are outgoing.

    {#blank#}4{#/blank#} People think heavy metal fans are very sad and unhappy. But like classical music fans, they are in fact easy-going and creative, and not very outgoing.

    {#blank#}5{#/blank#}Heavy metal fans in Sweden have more in common with heavy metal fans in Brazil than with Swedish fans of pop.

    195 countries reached an agreement(协议) on Dec. 12, 2015 after two weeks' talks in Paris. They talked about climate(气候) change. It is the first time in history that most of the world's countries, rich or poor, promised to take action to deal with climate problems.

    Below is a chart showing where the greenhouse gas(温室气体) comes from.

Where is greenhouse gas from?

    The Paris Agreement(巴黎协定) sets up a goal of cutting down the earth temperature to less than 2℃. If the warming gets above 2℃， there will be serious problems on the earth like natural disasters.

The agreement also asks countries to volunteer to do things. For developed countries, they will do even more. They have a plan to offer over 100 billion dollars to help poorer countries to develop clean energy like water and wind power.

    However, the Paris Agreement won't solve earth warming by itself. The future also depends on how well each country will carry out their promises.

    Republic of Kenya is a country in Africa, with a population of about 48,000,000. Nairobi is the capital of Kenya, Kiswahili and English are its official languages, and it also has many local languages. Kenya covers 582, 646 square kilometres. It has a warm and humid tropical climate on its Indian Ocean coastline. On Kenya's land, fruit, vegetables, coffee, tea, corns and wheat are the main agricultural produce. The people in Kenya like cross country running, road running, soccer, boxing and so on. Kenya won several medals during the Beijing Olympics, six gold, four silver and four bronze, making it Africa's most successful nation in the 2008 Olympics

Republic of Kenya

Capital: {#blank#}1{#/blank#}

Size: {#blank#}2{#/blank#}km²

Official languages: Kiswahili, {#blank#}3{#/blank#}

population: {#blank#}4{#/blank#}million

Sports: cross country running, {#blank#}5{#/blank#} soccer, boxing

    In the 13th century, the famous Italian traveler, Marco Polo, traveled a long way to China. During his stay in China, he saw many wonderful things. One of the things he discovered was that the Chinese used paper money. In Western countries, people did not use paper money until the 15th century. {#blank#}1{#/blank#}.

    A Chinese man called Cai Lun invented paper almost 2,000years ago. He made it from wood. {#blank#}2{#/blank#} He then put these pieces of paper together and made them into a book.

    {#blank#}3{#/blank#} We use a lot of paper every day. If we keep on wasting so much paper, there will not be any trees left on the earth. Every day, people throw away about 2,800 tons of paper. It takes 17 trees to make one ton of paper. This means that we are cutting nearly 48,000 trees every day.

    Since it takes more than 10 years for a tree to grow, we must start using less paper now. If we don't, we will not have enough time to grow more trees to take the place of those we use for paper.

    {#blank#}4{#/blank#} We can use both sides of every piece of paper, especially when we are making notes. We can choose drinks in bottles instead of those in paper packets. We can also use cotton handkerchiefs and not paper ones. When we go shopping, we can use fewer paper bags. If the shop assistant does give us a paper bag, we can save it and reuse it later.

    {#blank#}5{#/blank#} If we all think carefully, we can help protect trees. But we should do it now, before it is too late.