The original meaning of "Ke" here refers to level. "Shuowen": "Ke, Cheng Ye. From the grain to the bucket. The fighter is the measure. The bitter grain is cut." This word was originally a familiar word for measuring the grain and millet to evaluate the grade. In ancient books, the word "ke" often appears as the meaning of "level". For example, "The Analects of Confucius·Bayi No. 3": "Shooting does not focus on the skin, and the strength is different, which is the ancient way." "Shooting" refers to the archery ceremony, an ancient etiquette ceremony in the form of an archery competition. "Leather" means hitting the leather target. The meaning of this sentence is probably that the ancient people performed archery salutes mainly not to compete with each other to see who could hit the target more times. This is because different people have different strengths, and this competition is not harmonious. (My current understanding of this sentence largely refers to the views I originally read in a paper. The author is called Yang Yao. I would like to express my gratitude. In addition, the shooting ceremony should have been similar to that in "Homer's Epic" The aristocratic warrior competition event was originally about competing for superiority regardless of harmony or disharmony. The view here in "The Analects" is not credible.) Later, the meaning of "ke" was derived from this meaning to "examine and check". The "ke" in the "imperial examination" that we are familiar with is a further extension of the meaning of "examination". The solidification process of this word may indeed be influenced by the commonly used word "pediatrics" derived from traditional Chinese medicine. Due to the relatively high word frequency of this word, when talking about things at the level of children, the literal meaning of such a word is used casually, creating a layer of intentional or unintentional "punning". Similar language phenomena also exist.