The liver function two-and-a-half actually refers to hepatitis B two-and-a-half, or hepatitis B five, which mainly includes hepatitis B surface antigen, hepatitis B surface antibody, hepatitis B e antigen, hepatitis B e antibody and hepatitis B core antibody, through this test can determine the current status of hepatitis B infection and the status of the regression. For example, if only the first item is positive, it indicates the presence of hepatitis B virus infection; if only the second item is positive, it indicates that hepatitis B vaccination was given and antibodies were produced, or that hepatitis B virus infection was once acquired and a certain degree of immunity was present. If items 1, 3 and 5 are positive, this is hepatitis B major triple yang; if items 1, 4 and 5 are positive, this is hepatitis B minor triple yang, which indicates that it is currently in the acute and chronic hepatitis B infection period and is infectious. In particular, the hepatitis B major triple-positive, its viral replication and infectiousness is stronger, and it needs to be given antiviral treatment. However, hepatitis B two-to-one is only a preliminary test, and when abnormal results appear, further quantitative hepatitis B virus DNA testing should be performed to further guide clinical diagnosis and treatment.