Thump. Thump. That is the sound of your heart beating. What an amazing organ! It works all day. It works all night.
Your heart pumps(抽运) blood（血液） to all the parts of your body. It pumps blood to your head, your fingers and your f. And it weighs o about half a kilogram.
But it's a very s organ（器官）. It beats(跳动)100,000 times a day without stopping. That's 35 m times a year. Wow!
In your life, your heart will beat about two and a half billion times. You know what e is really amazing? Your heart d all of this without you even giving it a thought. It just keeps working.
Most hearts beat about 70 times e minute. See for yourself. Put your hand on your chest(胸膛). F your heart beating. Now, count how many times it beats in a minute.
Take care of your heart. Eat well. Sleep well. And do lots of e. That way, your heart will be h and keep working.
