In most parts of the world, many students help their schools make less pollution. They join “environment clubs”. In an environment club, people work together to make our environment clean.

    Here are some things students often do.

    No-garbage lunches. How much do you throw away after lunch? Environment clubs ask students to bring their lunches in bags that can be used again. Every week they will choose the classes that make the least garbage and report them to the whole school.

    No-car day. On a no-car day, nobody comes to school in a car. Not the students and not the teachers! Cars give pollution to our air, so remember: walk, jump, bike and run. Use your legs! It's lots of fun.

    Turn off the water! Did you know that some toilets can waste twenty to forty cubic (立方) meters of water an hour? In a year, it would fill a small river! In environment clubs, students mend those broken toilets. We love our environment. Let's work together to make it clean.

    Eighteen years ago, Terry Grahl, was pregnant with her fourth child. “Money was very tight,” Terry recalls. So when her mom called to ask if she'd like to go shopping at the local fabric(布料) store for the coming Christmas, she couldn't say no because she knew she badly needed some fabrics to make new clothes for her children. “I remember walking around, gazing at all this beautiful fabric, wondering whether there is anything cheap that I could afford. And I could still get some money left to buy Christmas gifts for my family.

    Well, Terry's mom must have known what Terry was thinking. Smiling kindly, she whispered to Terry, “You pick any fabrics you like. It's your Christmas gift from me.” Terry's eyes were filed with tears as the cart began to overflow with many fabrics, but not because Terry was planning on making herself a pretty dress or a pair of curtains for the kitchen. Rather, Terry's mom's kindness had inspired some holiday gift ideas in Terry, and it didn't take long for Terry to figure out what she was going to do with all that fabric.

    “I was going to make my first quilt,” she explains. “Every night I would work on this queen-size quilt. With every stitch(一针), I thought about all that my mom had done for me over the course of my childhood, during which we were always battling homelessness, but Mom somehow managed to fill our lives with love and make everything okay.”

    On Christmas Day, five days after her baby girl was born, Terry handed her mom a gift box. Inside was the quilt she had sewn, from the fabric her mother had given her as a gift.

    It's a warm summer afternoon. You're cooking up the catch of the day over a campfire. Suddenly, a few raindrops fall on your arms, and before you know it, the sky is opened up. Then you hear what sounds like thunder in the distance. What should you do? Your tent is close by and would offer shelter from the pouring rain. There's a campsite picnic shelter a few minutes down the path. And then you remember that your car is parked down the road. What's your safest choice to make sure you and your families are safe?

    It's a common question for many hikers(徒步者) and campers, especially when they are camping during summer months. Heading to your car is almost always the safest choice. Your tent and a picnic shelter will keep you dry, but they offer little or no protection against lightening. Your car, on the other hand, will keep you dry and protect you from lightening strikes. Protecting yourself against possible lightening strikes is very important; lightening kills an average of 62 people in the US each year. If you keep all of the windows and doors closed in your car, you'll be able to return to your campsite safely.

    Of course, if you're backpacking(背包旅行), not car camping, and you're deep in the woods, your car won't be a good choice. So, what should you do if your car is far away and there's no other safe shelter nearby? First, you'll have to make sure that tree limbs or other objects don't fall on you or your campsite. Then you'll have to get in a safe position to avoid lightening, or flash flood conditions. What else should you do?

    One morning, more than a hundred years ago, an American inventor called Elias Howe finally fell asleep. He had been working all night on the design of a sewing machine but he had run into a very difficult problem: It seemed impossible to get the thread to run smoothly around the needle.

    Though he was tired, Howe slept badly. He turned and turned. Then he had a dream. He dreamt that he had been caught by terrible savages whose king wanted to kill him and eat him unless he could build a perfect sewing machine. When he tried to do so, Howe ran into the same problem as before. The thread kept getting caught around the needle. The king flew into the cage and ordered his soldiers to kill Howe. They came up towards him with their spears raised. But suddenly the inventor noticed something. There was a hole in the tip of each spear. The inventor awoke from the dream, realizing that he had just found the answer to the problem. Instead of trying to get the thread to run around the needle, he should make it run through a small hole in the center of the needle. This was the simple idea that finally made Howe design and build the first really practised sewing machine.

    Elias Howes was not the only one in finding the answer to his problem in this way.

    Thomas Edison, the inventor of the electric light, said his best ideas came into him in dreams. So did the great physicist Albert Einstein. Charlotte Bronte also drew in her dreams in writing Jane Eyre.

    To know the value of dreams, you have to understand what happens when you are asleep. Even then, a part of your mind is still working. This unconscious(无意识的), but still active part understands your experiences and goes to work on the problems you have had during the day. It stores all sorts of information that you may have forgotten or never have really noticed. It is only when you fall asleep that this part of the brain can send messages to the part you use when you are awake. However, the unconscious part acts in a special way. It uses strange images which the conscious part may not understand at first. This is why dreams are sometimes called “secret messages to ourselves”.

    Here are some recommendations for tourists to choose from.

    Banff, Canada

    Banff, located in the Rockies, has a view of tall mountains, deep valleys and lakes, making it the first town to become part of the country's national parks. Tourists can enjoy its beauty by hiking, horse riding and boat trips. Banff was founded in 1883 while a railroad was in construction. It was the water springs that drew the engineers' attention to the place as a settlement. With such a fantastic view, it's no surprise that Banff hosts a number of cultural festivals.

    Lisbon, Portugal

    Lisbon is the capital of Portugal, with the warmest winters of any major European city.

    Belem Tower and Jeronimos Monastery are listed as UNESCO World Heritage Sites. The former was built in the 16^th century as a symbol of Portugal's Extraordinary Age and the latter is one of the greatest examples of the Portuguese late-Gothic style of architecture. The Lisbon Oceanaium is among Europe's finest aquariums. The Museum Calouste Gulbenkian is among the best museums in Europe containing priceless artworks covering 4000 years from ancient Egyptian times to the late 20^th century.

    Portland, US

    Portland is frequently recognized as one of the world's most environmentally-friendly cities because of its well-built pavements, large community of cyclists and convenient public transportation. Us climate is ideal for growing roses and it's called the “City of Roses”. Besides, the seaport is also known as a city of beer: it has the largest number of beer breweries（啤酒厂）of any city in the world. Today's Portland is better known for its music. It's called “the capital of karaoke” and “one of the most exciting music scenes” in the US.

    Bordeaux, France

    Bordeaux attracts tourists with its rich cultural heritage, especially its wealth of architectural treasures. Besides the Cathedral of Saint Andrew dating back to 12^th century, the Basilica of Saint Michael is another one of the city's UNESCO World Heritage Sites. It took 200 years to build from 14^th to 16^th centuries. Other significant buildings include the Grand Theater built in 1780 in the new Classical style and the Stone Bridge built in 1821.

    A primary school in Jinhua, Zhejiang Province has announced it no longer requires parents to sign their children's homework, which was aimed at getting parents to supervise(监督) their children after school. China Youth Daily comments: Putting an end to the requirement that parents sign off on the homework of their children eases the burden on many parents, as otherwise they would have to do primary school homework after a hard day's work. But there are worries that if parents stop having to sign off on their children's homework, the children will not get good grades.

    However, the most effective way for children to study is to develop their willingness to learn and do their own studies. When doing homework, students practice and hopefully apply what they have learned. It is true that teachers are supposed to check students' homework and identify their mistakes. But some parents correct their children's mistakes by themselves when signing off on it.

    It is the duty of students to do their homework, be responsible for their studies and correct their mistakes. Parents' supervising their homework, checking their answers and dealing with the harder problems will only make children less aware of their mistakes and encourage them to wait for their parents' help when they face any problems.

    Children have to manage their own learning and develop the ability to study by themselves, as competence will not be achieved if a student simply repeats strict tasks in which he is assisted in school by teachers and at home by parents.

    A delayed satisfaction experiment conducted by Walter Mischel in the 1960s proved that children with better self-discipline(自律) performed better in their studies and interpersonal relationships.

    There is little doubt that parents' supervision can make children's homework better. But it does not give children the chance to practice their ability to solve problems independently.