A hobby can be almost anything that a person likes to do in his free time. Hobbyists raise pets, watch birds, paint pictures, play the piano and grow flowers. They also go to concerts, climb mountains, go fishing, skate and swim. They collect everything from books to butterflies and from boxes to stamps.

    People follow hobbies because these activities offer enjoyment, friendship，knowledge and relaxation. Sometimes they even make money by following a hobby. Hobbies help people relax after hard work, and provide a balance between work and play. Hobbies also offer interesting activities for persons who are retired. Anyone, rich or poor, old or young, can follow an interesting hobby.

Hobbies can also help a patient to keep healthy. Doctors have found that hobbies are useful in helping patients (病人) recover from illness. Hobbies give patients who can't move around something to do, and provide interests that keep them from thinking about themselves. Many hospitals treat (治疗) patients by having them take up interesting hobbies. Anyone, old or young, sick or well, rich or poor, can follow a good hobby, in spite of his age, health or money.

    In early times, most people were too busy making a living to have many hobbies. But some persons who had spare time did enjoy hobbies. People today have more time than ever before for hobbies. Machines have now reduced much time that people must spend on their jobs. More people retire at an earlier age than before. Those who have developed hobbies never need to worry about what to do with their newly-found free time hours.

    Sir William Osler, a famous Canadian doctor expressed the value of hobbies by saying, “No man is really happy or safe without a hobby. ”

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What are fossils?

    Fossils are the remains of plants or animals. For such remains to be considered fossils, scientists have decided they have to be over 10,000 years old. The word fossil comes from the Latin word “fossilis”, which means, “dig up”.  Fossils can be divided into “body fossils” and “trace(痕迹) fossils”. Body fossils are the remains of a plant or animal's body. Trace fossils are the remains of the activity of an animal, such as footprints, egg shells, and nests.

How are fossils formed?

    Some animals were quickly covered after their death by sediment(沉淀物) like earth, mud or sand. Over time, the parts of the animals that didn't rot (usually the harder parts like bones and teeth) were covered in the newly formed sediment. Then, a lot of chemical changes happened to the animals bodies. Water with minerals(矿物质) went into the bone and took the place of the chemicals in the bone with rock-like minerals. In the end we get a heavy, rock-like copy of the original object - a fossil. There weren't any changes in size and shape when an object changed into a fossil, but the fossil of a bone doesn't have any bone in it! It is chemically more like a rock! According to scientists, fossils have been found on every continent(大陆) on Earth.

    In northern China during spring, big sandstorms often make trouble for people. When the sky is dark with sand, buses and cars all move much more slowly. Sometimes, people can't even see for 20 metres.

    Sandstorms usually happen in spring. Big sandstorms happened in more than 10 provinces in northern China last year. More than 70 million people have had problems in those places because of the sandstorms.

    People in southern China don't have to worry about this kind of bad weather. Most of the sand comes from the north of China. In northern China, lots of places have few trees and don't get much rain. People there have been cutting down too many trees. When there aren't many trees, the ground can't keep enough water. Over the years, the ground dries up and turns to sand. When spring comes and the ice melts (融化), the ground becomes looser (更松散的). Strong winds take the loose sand into the sky.

    Sandstorms are bad for people's health. If people take in too much sand, they could cough or have asthma (哮喘).

    Sandstorms also give farmers lots of problems. Sometimes their sheep get lost in the storms and never get back home. The winds also tear down farmers' houses.

    What can you do to stop sandstorms? Here's an idea: Ask your parents to help you plant some trees this spring.

    If you see people cutting down too many trees, tell them about the dangers of sandstorms, and ask your government to stop them from cutting.

    Each year more than2,500 people die and 12,600 are injured in home fires just in the UnitedStates, with direct property(财产) lossbecause of home fires at about $7.3 billion every year. Every day Americansexperience tile horror(惨状) of fires, but most people don'tunderstand fires.

    To protect yourself, itis important to learn something about home fires.

    In less than 30 secondsa small flame can get completely out of control and turn into a major fire. Itonly takes minutes for thick black smoke to fill a house or for it to be inflames. Most deadly fires occur in the home when people are asleep, lf yourealize a fire, you won't have time to take valuables because the fire spreadstoo quickly and the smoke is too thick. The fire uses up the oxygen you needand produces smoke and poisonous(有毒的) gases that kill. Breathing even small amounts of smoke and toxicgases can make you tired and sleepy, and short of breath. The smoke can causeyou to be a deep sleeper before the flames reach your door. You may not wake upin time to escape.

    Room temperatures in afire can be 100 degrees at floor level and rise to 600 degrees at eye level.Breathing in this super-hot air will burn your lungs. It can melt clothes toyour skin. In five minutes, a mom can get so hot that everything in it startsto burn at once.

    Fires are bright atfirst, but quickly produce black smoke and complete darkness. If you wake up toa fire you may be blinded, confused about where you are or which direction you shouldgo in and unable to find your way around the home you've lived in for years.

    Only when we know thetrue nature of fires can we prepare our families and ourselves.

    Developing healthy eating habits starts from childhood, therefore it is important for parents to teach and provide children with a healthy diet.

    DPHSS administrator of the Bureau of Nutrition Services, Charlie Morris said, "A healthy diet for a child always includes a lot of fruits and vegetables in the diet limiting the amount of simple sugars in the diet and high fat food and highly processed* food." This means staying away as much as possible from food such as chips, cookies, candies and sugary drinks, because all children need to have meals and the meals should be a well-balanced diet.

    Community nutritionist* Thelma Romoso said, "The fruit, the vegetable, the grain, the protein, and also the milk, the diary product are all necessary in the diet for a child. Among them, the fruit and the vegetable should come first. It's easy for a mother to go into the two plus three concept* of fruits and vegetables or five a day." This concept means that there are at least two servings* of fruits a day, three servings of vegetables a day which can be served for lunch and dinner.

    Morris also said that the child's hunger level influences how much is eaten and the parent controls what and when the meal is offered, saying, "Mom needs to make sure that the food offered is good food for the child to eat and she also needs to consider how active they are through the day. Snacks* are not a bad thing, so the mom should offer good kinds of snacks as well."

    When it comes to preparing your child's lunch and snacks for school, make sure to keep in mind that the food you provide should not only provide enough energy but also be healthy such as fresh fruits, and whole grain bread. But parents must be sure to remember that a good healthy diet must be balanced with physical activity, that is to say, it is important that children get outside and run around and play and get activity besides eating a good diet.