从前，在一个叫做杞国的地方，有一个名叫李明的男子。
他每天都非常担忧一件事情：他认为天空会塌下来，大地会裂开。
这种想法让他吃不下饭，也睡不好觉。
有一天，他的朋友张华听说了他的忧虑，就来和他谈心。
张华告诉李明：“其实天空是由空气堆积而成的，而空气是无处不在的，你不必担心它会塌下来。”
李明听后觉得有些道理，心情稍微放松了一些。
可是没过多久，李明又开始担心了。
他想：“如果天空真的是由空气构成的，那么会不会因为承受不住太阳、月亮和星星的重量而坠落呢？”
张华听到这个问题，耐心地解释道：“太阳、月亮和星星只是空气中发光的部分，即使它们掉下来，也不会对我们造成伤害。”
李明听了这些话，心里的疑虑减轻了许多。
但他又想到了另一个问题：“那大地会不会裂开呢？”
张华想了想，回答说：“大地向四面八方延伸，每一寸土地都紧紧相连，你看我们每天都在上面行走，它怎么会裂开呢？”
李明听完这番话，心中的大石头终于落地了。
从那以后，人们根据这个故事，创造了一个成语“杞人忧天”。
这个成语告诉我们，不要过于担忧那些不切实际的事情，否则只会给自己带来不必要的烦恼。
Once upon a time, in a place called Qiguo, there was a man named Lee Ming.
He worried about one thing every day: he believed that the sky would fall and the earth would crack open.
This thought made him lose his appetite and sleep poorly.
One day, his friend Zhang Hua heard about his worries and came to talk with him.
Zhang Hua told Lee Ming, "In fact, the sky is made up of layers of air, and air is everywhere. You don't have to worry about it falling down."
Lee Ming felt some relief after hearing this explanation.
But soon enough, he started worrying again.
He thought, "If the sky is really made of air, won't it collapse under the weight of the sun, moon, and stars?"
Zhang Hua patiently explained, "The sun, moon, and stars are just the shining parts of the air. Even if they fell, they wouldn't harm us."
After hearing these words, Lee Ming's doubts were greatly reduced.
But he had another question: "What if the earth cracks open?"
Zhang Hua thought for a moment and replied, "The earth stretches in all directions, and every inch of land is tightly connected. Look, we walk on it every day. How could it crack open?"
After hearing this explanation, Lee Ming's heart was finally at ease.
From then on, people created a proverb based on this story: "The Qiguo man worries about the sky".
This proverb teaches us not to overly worry about unrealistic things, or else we'll only bring unnecessary troubles upon ourselves.
