Why ask qingquan, because there is running water at the source?

Why do you ask qingquan? It means asking why the water in the pond is so clear, because there is an inexhaustible source to supply it with living water.

I don't know where the clear spring is, because there is flowing water from the source, which comes from Zhu's "Random Thoughts on Reading".

The whole poem "Reading Feeling, Part I" takes Tang Fang as a metaphor, which vividly expresses a subtle and unspeakable reading feeling.