Hundreds of years ago, life was harder than it is today. People didn't have modern machines. There was no modern medicine, either.

    Life today has brought new problems. One of the biggest is pollution. Water pollution has made our rivers and lakes dirty. It kills our fish and pollutes our drinking water. Noise pollution makes us talk louder and become angry more easily. Air pollution is the most serious kind of pollution to all living things in the world.

    Cars, planes and factories all pollute our air every day. Sometimes the polluted air is so thick that it is like a quilt (被状物) over a city. This kind of quilt is called smog.

    Many countries are making rules to fight pollution. Factories must now clean their water before it is thrown away, and they mustn't let dirty smoke go into the air.

    We need to do many other things. We can put waste things in the dustbin and do not throw them on the ground. We can go to work by bus with our friends in the same car. If there are fewer people driving, there will be less pollution.

    Rules are not enough. Every person must help to fight pollution.

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    Do you and your friends ever talk about your dreams with each other? If you do, you might have noticed something interesting – some of your friends seldom remember their dreams, but some can always describe their dreams so clearly that it seems like they're describing things that really happened to them. What makes those people different?

    The answer is simple. There are two different types of dreamers – low dream recallers（回忆者）and high dream recallers.

    Low dream recallers usually remember their dreams only twice a month. But high dream recallers are able to remember them about five mornings a week. And a new study suggests that activity in a certain part of the brain could have something to do with it, reported The Huffington Post.

    Perrine Ruby, a French researcher at the Lyon Neuroscience Research Center, studied 41 people (21 high dream recallers and 20 low dream recallers) and recorded their brain activity.

    She found that a part of the brain called the temporo-parietal junction (颞顶联合区) was more active in high dream recallers than in low dream recallers – both when they were sleeping and awake.

    This brain area collects and processes（编程）information from the outside world. This means that high dream recallers know more about what's happening around them. For example, when they are awake, they respond (对……有反应) more strongly to hearing their own names, and when they are sleeping, they are woken more easily by sounds and movements.

    By closely studying people's brain activities, Ruby found that high dream recallers have twice as much “wakefulness time” during sleep as low dream recallers do. And it is during these short times of wakefulness that the brain remembers dreams.

    “The sleeping brain is not able to remember new information,” Ruby told The Washington Post. “It needs to wake up to be able to do that.”

    This is not hard to understand. Just try to think of your own sleeping experiences. If you are worried during the night, you are more likely to remember your dreams, but if you sleep well, you will remember little in the morning, and this is because “you never get a chance to remember”, Robert Stickgold, a Harvard Medical School researcher, told The Washington Post.

    Most American children eat potatoes. But many children don't know what of the potato is the best food. Take a knife and cut from the middle of the potato a piece as thin as paper. I hold the piece between your eyes and light. You will see that the potato has skin(皮), an outside rim(边缘)and an inside part. The outside rim which is right under the skin of the potato, is the most valuable part of all. But this is often thrown away with the skin. Even the skin itself is better for food than the inside. When eating a cooked potato, if you choose the inside and leave the outside, you are throwing the best part of it. If you can't cat the whole potato, eat the outside rim first and leave the inside part.

    When someone says, "Well, I guess I'll have to face the music", it doesn't mean that he is planning to go to hear a singer or attend a concert. It is something far sadder than you are called in by your leader to explain why you did this and that or why you did not do this or that.

    At some time or another, every one of us has to "face the music", especially as children. We can all remember Father's angry words "I want to talk to you". And only because we did not listen to him. What a bad thing it was!

    In the middle or at the end of every term, we students have to "face the music". The result of the exam will decide whether we will face the music or not. If.…that means parents' cold faces and contempt (轻蔑) of the teachers and classmates.

    The American novelist James Fennimore Cooper said in 1851 that the expression "face the music" was first used by actors while waiting aside to go on stage. When it was their turn to go on the stage, they often said, "It's time to face the music." An actor might be frightened or nervous as he moved onto the stage in front of the audience because they might be friendly, or perhaps they are hostile, especially if he forgot what he would say. But he had to go out. If he did not, there would be no play. He would lose his job.

    "To face the music" is well known to every American, young or old. It is at least 100 years old. It really means that you have to do something, no matter how terrible the whole thing might be, because you know you have no choice.