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| 电子课本 | 课文音频 |
Unit 3 Healthy Body, HealthyMind
We all know exercise is important, yet we don’t always want to do it! Often we are too busy or feel lazy. We should try our best to exercise every day.
Exercise is good for our body. When we exercise, our body changes. Exercise develops our muscles and makes us stronger. When we exercise, we use energy, this makes knees on weight down. Being overweight puts stress on our body. It can cause pain in our back and knees, and even cause more serious problems such as heart disease later in life.
Exercise is also great for our brain. During exercise, our heart beats faster and we breathe harder. Our brain gets more oxygen because of this, and that helps our memory improve. Scientists also tell us the body make more of certain chemicals after exercise. This helps us to learn and think well. So when you have trouble with your homework, do some exercise, then try again!
Exercise also helps us to feel happier. When we exercise, our brain makes special chemicals. This chemicals can relax our body and calm our mind. Feeling fit can also make us feel better and more confident about ourselves. When we play sport with others, we can even make new friends.
Remember: Health is wealth! The more you exercise, the healthier you become. Try to make exercise a part of your life!
---汉语翻译---
身体健康，心灵健康
锻炼对我们的身体有好处。当我们锻炼时，我们的身体会发生变化。运动能锻炼我们的肌肉，让我们更强壮。当我们运动时，我们会消耗能量。这可以减轻我们的体重。超重会给我们的身体带来压力。它会导致背部和膝盖疼痛，甚至在以后的生活中引起更严重的问题，如心脏病等。
锻炼对我们的大脑也大有裨益。在运动过程中，我们的心跳加快，呼吸也更用力。因此，我们的大脑获得了更多的氧气，这有助于提高我们的记忆力。科学家还告诉我们，运动后身体会产生更多的某些化学物质。这有助于我们更好地学习和思考。所以，当你做家庭作业遇到困难时，做一些运动，然后再试一次!
锻炼还能让我们感觉更快乐。当我们运动时，我们的大脑会产生特殊的化学物质。这些化学物质可以放松我们的身体，平静我们的心灵。感觉健康也能让我们感觉更好，对自己更有信心。当我们和别人一起运动时，我们甚至可以交到新朋友。
记住:健康就是财富。你锻炼得越多，你就变得越健康。试着让锻炼成为你生活的一部分吧。
---good luck---
