Sharks (鲨鱼) are the most frightening animals in the sea. Sometimes we can see sharks swimming in the sea around Hong Kong. People put nets around some beaches to protect swimmers. When there is a "shark's flag", people must stay on the beach. It will be too late if a shark can swim sixty kilometers an hour to you.

    There are 30 kinds of sharks and 25 kinds of them are dangerous. The whale sharks are very big. They can grow to 18 meters long, but they are not dangerous to people. The jaws (大白鲨) and the tiger sharks are the most dangerous kinds of sharks.

    Do you know all sharks must keep swimming, or they will go down? All sharks can feel everything that happens around them. We must keep calm and don't make any noise when a shark is swimming near you.

    If a shark loses a tooth, a new one will grow out very quickly. So sharks always have many sharp teeth.

    Animals can move from place to place, but plants cannot. When an animal is under attack, it can run away or fight back. Plants certainly cannot run away, and they have no teeth or claws. But plants can protect themselves in both physical and chemical ways.

    Some plants have their own ways to keep animals away. For example, the leaves of the holly(冬青) have sharp prickles(刺) that discourage grass-eating animals. Holly leaves on lower places have more prickles than leaves on upper places. This is because the lower leaves are easier for most animals to reach. Some plants, such as the oak trees(橡树), have thick and hard leaves that are difficult for animals to eat. Some grasses may contain a sandy material, and eating such grasses wears down the animals' teeth. Many plants also have chemical defenses. Some plants produce chemicals that taste bitter(苦) or cause an unpleasant reaction. Some plants may fight against an attack by increasing the production of these chemicals. When a worm bites a tobacco leaf (烟叶), the leaf produces a chemical smell. Many plants depend on both physical and chemical defenses. A certain plant in China, for instance, has prickly leaves, and each prickle has poisonous water(毒液). Only one experience with this kind of plant will teach an animal to stay away from it in the future.

    We all want to protect the environment, but we're mostly too busy or too lazy to put up big change. There is nothing new here but if you follow at least some of these tips, you can be proud of yourself in the protection of the environment.

    Use LED light bulbs: They last much longer and they can save energy.

    Donate: You have many clothes or things you want to throw. If they are still usable, give them to someone who needs them.

    Turn off your devices: When you do not use a house device, turn it off. For example, if you don't watch TV, turn it off. Turn off the light when you leave a room.

    Walk or cycle: Driving is one of the biggest causes of pollution. If you want to use your car, ask yourself the following question: do I really need my car? Walk or use your bike if the journey is a short one.

    Detergent (洗漆剂):Use less dose of detergent to wash your clothes or dishes.

    Leaky faucets(漏水龙头):Fix them, or they will waste a lot of water.

    Rainwater: Think of collecting rainwater. This water can be used for different purposes.

    All these tips will help you save money and protect the environment.

    How green are you？Do you know how to be green？

    We all need a healthy environment, but we produce waste every day and it does harm to our environment. Though we are young, we can still do something to help. In fact, even the simplest everyday activities can make a real difference to the environment. Here are some ideas for you.

    Reduce

    Reduce means" use less". Don't waste things. This saves money and reduces pollution and waste going into the environment. Before we buy something new, think whether it is really necessary﹣or maybe the old one will be just as good! When we do buy things, choose local products if possible, and try not to buy too many things from abroad.

    Reuse

    Reuse means" use again". Use things for as long as possible. When we buy things, make sure that they last a long time. We should look after them so that they will last, and we should repair them if we can instead of throwing them away and buying new ones. Don't use a paper cup of a paper bag. It's better to use a china cup and a lunch box because you can use them again.

    Recycle

    Recycle means" change things into something else". Though it takes energy to change something into something else, it's better than throwing things away or burning them. Find out what can be recycled in your neighborhood and take part in recycling programmes. We should also buy products made from recycled materials, such as recycled paper, to help save trees.

    So please remember these three words: reduce, reuse and recycle.