Gram staining: gram staining is a differential staining method widely used in bacteriology. Bacteria are dyed by alkaline dye crystal violet and then dyed by iodine solution and then decolorizing with alcohol. Under certain conditions, some bacteria mordant color will not be removed, some can be removed, the former is called Gram-positive bacteria, and the latter is Gram-negative bacteria. In order to facilitate further observation, after decolorizing, the alkaline tomato red was reused, and the positive bacteria were still purple, and the negative bacteria were dyed red. This is the principle of Gram's dyeing. The steps include four steps: initial dyeing, mordant, decolorization and reproduction. The main steps are as shown in the diagram. Although spores can be seen in Gram stain, special spores can be used to make spores and mycelia in different colors when they are not easily observed. The main method of malachite green spore staining staining and phenol fuchsin staining method. The specific steps of the coloring method of malachite green are: first, after the smear of the inclined surface of the spore, the 10min is dyed with the green water solution of the saturated peacock, then flushed with tap water, and then washed with 0.5% red liquid, then 30s, washing and drying. The spores are green, mycelium and spores at the time of microscopic examination. The sac was reddish. The specific steps are as follows: first, according to the conventional smear, then add stone carbonate to the smear, and then slowly heat it under the slide to make the dye steam but not boil, and continue to add the dye, not to dry the dye liquid on the smear, so as to keep the 5min. After the smear is cooled, the dye is tilting, and the acid alcohol decolorization refers to the elution of the non red dye. Then the dye is washed thoroughly. After washing, the 2-3min is repeated with LV's methylene blue and the water is washed and sucked to the mirror. The cysts are blue and the spores are red in the mirror examination.