This sentence comes from "Three Kingdoms·Wei Zhi·Biography of Wang Su" written by Chen Shou of the Western Jin Dynasty, but it was not said by Wang Su, but by Dong Yu.

Original text

Dong Yu, whose courtesy name is Jizhi, is quiet and eager to learn. There are people who are scholars but refuse to teach. They say, "You must read it a hundred times first!" He says: "Read it a hundred times, and its meaning will become apparent to you." Scholars say: "Bitterness and thirst without daylight." When you hear the words "Three excesses," you may ask what the meaning of "three excesses" means. "Winter means the remainder of the year, night means the remainder of the day, and cloudy and rainy weather means the hour." Yu Ye."

Translation

Dong Yu, courtesy name Jizhi, has an honest and honest character and is very studious. Scholars nearby asked him to give lectures, but he refused to teach, but said to them: "Read it a hundred times, and its meaning will become apparent." The person who asked for advice said: "(What you said makes sense), but I just don't have time." Dong Yu Said: "You should use 'Sanyu' time." Someone asked what "Sanyu" is? Dong Yu said: "Sanyu is three kinds of free time. In winter, there is not much farm work. This is the free time of the year; at night, it is inconvenient to work in the fields, so this is the free time of the day; on rainy days, it is not easy to go out to work, It is also a kind of free time.

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