杞人忧天，是汉语成语，读音是qǐ rén yōu tiān，意思是总是去忧虑那些不切实际的事物。杞人忧天是《列子·天瑞》篇中的一则寓言，后来成为一个固定成语，常用来讽刺那些不必要的担心，但也有人用其表达一种忧患意识。
To worry about the sky is a Chinese idiom with the pronunciation of qǐ rén yōu tiān, which means to always worry about those unrealistic things. Worrying about the sky is a fable in “Liezi Tianrui”, which later became a fixed idiom, often used to ridicule those unnecessary worries, but some people use it to express a sense of worry.
There is a man in Qiguo who is worried that after the world collapses, there is no place for his body to sustenance, and he cannot sleep and eat.
There are people who are worried about his worries, so he went to enlighten him, saying: “Heaven is just a gas accumulation, there is no place where there is no gas. You stretch your limbs, move your breathing, and move in the sky all day. Why are you worried? What about the collapse and fall?”
The man said: “If the sky is gas, shouldn’t the sun, moon, stars, and stars fall down?”
The person who enlightened him said: “The sun, the moon, the stars, and the stars are also things that glow in the gas. Even if they fall, they cannot cause you harm.”
The man said, “What should I do if the land collapses?”
The person who enlightened him said: “The ground, the accumulated clods, is full of all directions. There is no place where there are no clods. If you step on (on it) and move on the ground all day, why do you worry about collapsing?”
(After an explanation by this person) that person is very happy to eliminate worries; the person who enlightened him is also very happy to eliminate worries.