根据短文理解，完成下列各题。
    In every school there is "top" crowd that sets the pace, while the others follow their lead. For example, if the crowd decides that it is smart to wear bright red sweaters, then very soon everybody is wearing bright red sweaters.
    There is nothing wrong with that, except the fact that for some people bright red sweater is really unsuitable.
    The situation can even become dangerous, if the top crowd decides that it is smart to drink and to drive cars at seventy miles an hour. Then the people who follow the lead are endangering their lives. They are like the sheep being led to the slaughter(屠杀).
    Now it's possible that you have come across situations like these more than once in your life. In fact you probably did something you knew to be wrong one time or another. You may have excused yourself by saying, "Gee, the crowd does it."Well, let the crowd do it, but don't do it yourself. Learn to say "No".
    Develop your own standards(标准)and your own judgment. If you know the crowd is planning something you disagree to, you'd better take the courage to bow out in a polite way. You'll have the satisfaction of standing on your own two feet.

  Turns out，you're not just what you eat—you're also where you eat．

  Researchers found out that people had double the number of calories(卡路里)when standing in a messy kitchen compared to when they stood in an orderly one．

    The researchers had 98 women spend to minutes in kitchens，under the guise of (以……为幌子)asking them to wait for someone．Half of the women stood in a messy kitchen，with piles of newspapers，dirty dishes and a ringing phone．The other half of the women waited in a clean kitchen．

    Both kitchens had bowls of biscuits and carrots．Each woman in the messy kitchen ate twice as many cookies compared to those in the clean kitchen．

    Why did this happen?

    “Being in a messy environment and feeling out of control is bad for diets，''Lenny Vartanian，one of the researchers，said．“It seems to lead people to think，‘Everything else is out of control,so why shouldn't I be?'''

    The study's size was small，but the findings prove something we know all too well：Stress(压力)is bad for you．Stress often causes people to overeat．Beyond weight gain，too much stress can also increase a person's heart rate，and lead to painful conditions like headaches．

    While there are many ways to manage stress．including listening to music and exercising，this study shows that there are easy and quick things you can do to find calm．The next time you don't want to tidy up the kitchen，remember that the exercise will help you a lot in so many ways．

    Noise pollution is doing much harm to our health now. Noise, in fact, is unwanted sound and is a kind of invisible (无形的) killer. More and more students enjoy listening to music very much. When they listen to MP3 players, they like to turn up the volume (音量). Some people love listening to loud music. Furthermore, while watching TV, they keep the volume up. But they haven't realized that the noise is weakening their hearing. In fact, the noise not only influences each member in the family, but also makes a difference to the comfort of neighbors.

Noise pollution is a source of increasing misery (痛苦) to people in our society. If people are often disturbed by it, they may feel uncomfortable or upset. What's worse, the noise can make people mad sometimes. If a worker works in a printing factory for too long, his/her hearing loss is much faster than a common person working in a quieter environment. So everybody must pay more attention to noise pollution. Generally speaking, the following four types of noise should be watched out for:

    ◆Noise in the street

    ◆Construction site (建筑工地) noise

    ◆Noise at work

    ◆Transportation noise

    I think the local department (部门) should take measures to control the noise levels, but it's everybody's duty to keep a quiet environment.

    People can use the phone to talk with others almost anywhere on the earth. But when you use the phone, you don't see the person you are talking with.

    Today some people are using a kind of telephone called the picture phone or vision phone. With it, two people who are talking can see each other.

    Picture phones can be useful when you have something to show the person you're calling. They may have other uses in the future. One day you may be able to ring up a library and ask to see a book. Then you'll be able to read the book right over your picture phone. Or you may be able to go shopping through your picture phone. If you see something in the newspaper that you think you want to buy, you'll go to the phone and call the shop. People at the shop will show you the thing you're interested in right over the phone .You'll be able to shop all over the town and never even leave your room.

    Do you still get free plastic bags from the supermarkets? Things have changed.

    China has banned(禁止) free plastic bags at shops and supermarkets, and people have to pay for using plastic bags. The rule started on 1st June. It came because our country tried to make litter less. Making super­thin(超薄的)plastic bags has also been banned.

    The Chinese once used about 3 billion plastic shopping bags a day, and they have caused pollution of the environment. The bags have become a main cause of plastic pollution because they are easy to break and people throw them away here and there. So the Chinese people are encouraged to bring their own bags for shopping.

    What kind of shopping bag is the best to bring? Some students in Chongqing have a good idea. They make their own shopping bags. They use old clothes to make cloth bags(布袋), and send them to their parents as presents. They also ask their parents and friends to use cloth bags instead of plastic ones. They think it is their duty to protect the environment.