Groups whose bowels are not prepared before the colonoscopy need to delay the examination and continue with the bowel preparation until a clear watery stool is passed before the colonoscopy can be performed. Bowel preparation, i.e., evacuation of the bowel, is required in advance before colonoscopy, in order to provide a good view for the operating physician, so as not to miss any lesions. The most common choice of diarrhea medication for bowel evacuation is compounded polyethylene glycol electrolyte bulk, which should be used under the supervision of a specialist physician. Most people can excrete watery contents after more than ten times, indicating that the intestinal tract has basically been emptied. However, there are a few people who still do not have a clean bowel when approaching the scheduled colonoscopy time, so they need to delay the time of colonoscopy and continue to prepare the intestinal tract. It is suggested that such groups can drink more water, walk around appropriately, massage the abdomen, etc., which can promote intestinal motility and facilitate the elimination of intestinal tract.