在游乐园乘坐过山车时，游客会出现心跳加快、呼吸急促的现象，该生理现象的发生主要依赖于

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    It's very important(重要的) for us to be healthy. Now I'll tell you how I can be healthy. I often eat fruit and vegetables. I don't like to eat hamburgers. They are not good for my health. I have a balanced diet. Many foods are important, such as rice, meat, eggs, vegetables and fruit. I like to eat apples. As the saying(谚语) says, “An apple a day keeps the doctor away.” And I also like doing sports. I like running in the morning. I play basketball in the afternoon with my friends. And sometimes I play ping­pong with my family at the gym on Saturdays. I think I'm healthy and strong. What about you?