Most animals have little connection with animals of a different kind, unless they hunt them for food. Sometimes, however, two kinds of animals come together in a partnership (伙伴关系) which is good for both of them. You may have noticed some birds sitting on the backs of sheep. This is not because they want a ride, but because they find easy food in the parasites (寄生虫) on sheep. The sheep allow the birds to do so because they remove the cause of discomfort. So although they can manage without each other, they do better together.

    Sometimes an animal has a plant partner. The relationship develops until the two partners cannot manage without each other. This is so in the corals(珊瑚) of the sea. In their skins they have tiny plants which act as “dustmen”, taking some of the waste products from the coral and giving in return oxygen which the animal needs to breathe. If the plants are killed, or are even prevented from receiving light so that they cannot live normally, the corals will die.

    Each year there is an increasing number of cars on roads and streets as millions of new cars and trucks are produced. One out of every six Americans works at putting together the parts of cars, driving trucks, building roads or filling cars and trucks with gas. Americans won't live without cars!

    Most Americans would find it hard to think what life would look like without cars. However, some have realized the serious problems of the air pollution that is caused by the car.

    The polluted air becomes poisonous and dangerous to health.

    One way to get rid of the polluted air is to build a car that does not pollute. That's what several of the large car factories have been trying to do. But to build a clean car is easier said than done. Progress in this field has been slow.

    Another way is to take the place of the car engine by something else. Inventors are now working on steam cars as well as electric cars. Many makers believe that it will take years to develop a practical model that pleases man.

    To prevent the world from being polluted by cars, we'll have to make some changes in the way many of us live. Americans, for example, have to cut down on the number of their total cars. They are encouraged to travel and go to work by bicycle. Bicycling is thought to help keep the air clean.

    But this change does not come easily. A large number of workers may find themselves without jobs if a car factory closes down. Thus the problem of air pollution would become less important than that of unemployment.

    Although cars have led us to a better life, they have also brought us new problems.

    As the weekend approaches, perhaps you're looking forward to a meal out or sitting in front of the TV with a takeaway. But as you settle down to enjoy that comforting plate of beef or start spooning that fragrant lamb curry over the rice, will you be worrying about whether you are really eating what was written on the menu?

    Yesterday it was revealed by the Food Standards Agency that more than a fifth of the 665 meat samples tested last year contained DNA from animals not listed on the label. Of the 145 problem samples, 73 came from supermarkets, while 22 came from processing plants. The remaining 50 all came from restaurants.

    I have no doubt that over the next few years, the percentage of meal coming from dubious origins will continue to rise unless something drastic is done. Why? There are two main reasons. First, too many businesses are willing to boost their profits by adulterating their products in the meat industry. I believe there is a systemic problem within the meat industry that makes it particularly attractive to unscrupulous characters who are really nothing more than criminals，the second is the complexity and length of the meat supply chain. If you buy a chicken-based ready meal from a supermarket, as you might imagine, that chicken will pass through many hands before it ends up on your plate here. Worse still, the meat will often he partially processed somewhere along that chain—usually with salt and water added to boost flavour and volume—which is quite legal.

    Obviously, it is impossible for consumers to be detectives about every piece of meal they eat.

    However, what you can do is to avoid processed foods and never buy ready meals. Stay away from burgers made in factories. Don't go to chain restaurants. Instead, go to local, independent restaurants where it is more likely the chef and owner—often the same person—cares about where the meat comes from, and will be happy to tell you. So, try to buy your meat from a good local butcher.

    And no, what I am suggesting is not going to hurt your purse or wallet. The essence, then, is to buy meat that has had as small a journey from field to fork as possible, because that is the only way you can he sure of what you eat. It's that simple.

    Chinese high school students have the longest study hours compared to their peers (同龄人) in Japan, the US and the Republic of Korea, a survey conducted by the four countries said.

    The survey, released by the China Youth and Children Research Center (CYCRC) on Monday, was jointly conducted with institutions in the four countries in September—October of 2008. It covers nearly 4, 000 students in senior high schools and vocational high schools in the four countries.

    About 78.3 percent of Chinese students said they spend more than eight hours at school and 56.7 percent said they study at least two more hours each day at home. By contrast, only 24.7 percent of their peers in the US, 20.5 percent in Japan and 15.4 percent in Korea study more than two hours after school.

    Around 60 percent of all students surveyed said their burden for studies was the heaviest; however, the Japanese felt their burden was the worst with respondents (应答者) reaching 79.2 percent.

    Among the five biggest headaches for young people in the four countries were: over—scheduling ranked first, followed by a boring leisure life, unsatisfied appearance, little time for exercise and making friends, and no spare money.

    "Moderate (适度的) study pressure can better drive students to develop, however, too much will squeeze (挤) their development space, and can even cause harm to their physical and psychological health," the survey said.

    "Balancing their studies and all-round development is a very important task," it said.

Throughout our lives,we have been told to take care of our physical health.But what is often ignored is mental health.That's why World Mental Health Day was created.{#blank#}1{#/blank#}.

When is World Mental Health Day?

World Mental Health Day is on October 10th.Though there is one specific date for it,it is often times celebrated and observed over the course of a week.{#blank#}2{#/blank#}, it allows more people to know about the importance of mental health and it educates the public about the "why", "how" and "what" of mental health.

What is the history of World Mental Health Day?

{#blank#}3{#/blank#}.When it first started,the day had no theme,but instead was an excuse for medical workers to educate the public on what was not always openly discussed — what mental health is and the issues that surround it.Mental health affects everything from our emotional state to our physical state,and everything in between.In the first few years,organizers usually hosted a global live broadcast,leading to live telephone participation from all over the world.

{#blank#}4{#/blank#}?

You can volunteer in or donate some money to mental health services to improve the livelihoods of people struggling with mental illnesses.Besides,too often we are too busy to slow down and take a breath.If you take a mental health day,you are giving yourself the space to grow and take care of your mental health.Lastly,you should check on your friends.Go for a walk with them or have an extended phone conversation if you are far away.{#blank#}5{#/blank#}.

A.Why mental health is so important

B.How to observe World Mental Health Day

C.By celebrating it in a week instead of a day

D.If we value the importance of mental health

E.The first World Mental Health Day began in 1992

F.In this article,let's explore World Mental Health Day

G.You might be surprised at how much you can help them relax