Do you ever find yourself getting really unhappy for almost no reason? Or suddenly feeling down without knowing why? Going from sadness to anger to joy in a matter of minutes can make many teens feel as though they're losing control. But why is the feeling so common among teens?

    Maybe you're starting a new school and not able to see old friends as much. Getting good grades or wanting to be better in sports or other activities can be a concern (关注) for many teens.

    Being accepted by friends is important. Teens also may notice, for the first time, a sense of distance from parents and family. You may feel you want to be on your own and make your own decisions, but it can also seem a bit lonely at times.

    Another important cause for mood swings is biology. When puberty (青春期) begins, the body starts producing hormones (荷尔蒙). These hormones cause physical changes in the body. But in some people, they also seem to cause emotional (情绪的) changes.

    Here are some things you can do that might make those bad moods a bit easier to deal with.

    Recognize you're not alone. Although not every teen experiences mood changes to the same degree, they are common.

    Talk to people you trust. Friends can help each other by realizing that they're not alone in their feelings. Talking to parents is important, too. Parents can share their own experiences dealing with bad moods. Teachers are often good resources and a doctor can help to answer questions about development.

    Get enough sleep. Though it can be hard to find enough time, getting enough rest is very important. Being tired can lead to more sadness.

    Create. Taking part in some kinds of activities, like building something out of wood, or starting an art or music piece. Writing can help you organize and express your thoughts and feelings. Get your thoughts on paper. Do the same thing with paint, music, or other art forms. Put your feelings into your artwork.

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