From the Southern Song Dynasty Zhu's "Rules of Training and Learning": When reading, you should read every word loudly and make no mistakes. You can't miss a word, you can't pour a word, and you can't be far-fetched. As long as you recite it several times, it will be catchy and unforgettable. The ancients said, "Read it a thousand times and see what it means." If you read well, you don't need to explain yourself. I have tasted that reading has three meanings: heart, eyes and mouth. If the heart is not here, the eyes will not look closely, and the heart will not be single-minded but will read freely. You must never remember it or keep it for a long time.