From which poem does "a leaf falls to know the autumn on earth" come?

From "Huai Nan Zi said the mountain motto": "See the big from the small, and know the old when you see a leaf fall."

"Luwen" quoted a poem from the Tang Dynasty: "A monk in the mountain doesn't know the number of children, but a leaf can tell the autumn on earth."

"Taiping Magnolia" Volume 24 quotes "A leaf falls and you know the autumn on earth."

1, Yiyi knew the arrival of autumn from the falling of a leaf. Metaphor through individual subtle signs, we can see the development trend and results of the whole situation.

2. The idiom "Better a broken jade than a broken one"

Make sentences:

1. The end of one season is the beginning of the next. Quite critical, I know winter is coming.

2. Crucially, prices have risen and civilians have suffered.

A yellow leaf falls from the tree, and then an autumn wind hangs. It's really quite critical!

But the signs before the storm may make us more picky.

5. The so-called critical events reflect that there are some problems worth pondering in China's social governance.